Personal Finance Deep Dive

The Biggest Money Mistakes at Every Age

And Exactly How to Fix Them

30 mistakes across 5 decades of life. Each one with real math, real psychology, and a real fix. Written by a former hedge fund manager who has seen every single one of these up close — including in his own portfolio.

Total Mistakes

across all decades

$3.2M

Most Expensive

lifestyle inflation in 20s

401K Match

Easiest Free Money

instant 50-100% return

HSA

Best Hidden Account

triple tax advantage

🎓

Your 20s

8 common mistakes · Ages 20-29

Your 20s are the most powerful decade for building wealth — not because you earn the most, but because time is on your side. Every dollar you invest at 22 has 40+ years to compound. The mistakes you make here echo louder than any other decade.

#1Not Starting to Invest Immediately

Impact💰💰💰💰💰

Why People Make This Mistake

You think you don't have enough to invest, or that you'll 'start later when you make more.' The psychology is understandable — you're young, broke, and investing feels like something adults do. But compound interest doesn't care about your feelings.

💸 The Real Cost

If you invest $200/month starting at age 22 vs. age 32 (both at 10% avg. return), by age 62 you'd have $1,264,000 vs. $456,000. Waiting ten years costs you over $800,000. The first $200/month you ever invest is literally the most valuable money you'll ever put to work.

✅ The Fix

Open a brokerage account today. Literally today. Put in $50. Buy a share of VTI or VOO. Set up automatic monthly investments. The amount barely matters — the habit is everything.

🎯 Glen's Take

“I started investing at 19 with a few hundred bucks and eventually ran my own hedge fund. The single biggest advantage I had wasn't intelligence or connections — it was starting early. My first investments were terrible, but the lessons compounded even faster than the money.”

#2Not Negotiating Your First Salary

Impact💰💰💰💰💰

Why People Make This Mistake

You're just grateful to have a job. You don't want to seem 'greedy' or 'difficult.' So you accept the first number they offer. This is one of the most expensive acts of politeness in human history.

💸 The Real Cost

A $5,000 difference in your starting salary, compounded over a 40-year career with 3% annual raises, means roughly $600,000 in lost lifetime earnings. Your first salary is the base that every future raise, bonus, and 401K match is calculated from.

✅ The Fix

Research market rates on Glassdoor and Levels.fyi before any interview. When they make an offer, say: 'I'm excited about this role. Based on my research, I was expecting something closer to $X. Is there flexibility?' The worst they can say is no.

🎯 Glen's Take

“I negotiated my salary exactly once in my career and it was the best financial decision I made that year. The manager literally said 'I was hoping you wouldn't ask.' They had budget. They always have budget.”

#3Lifestyle Inflation With Your First Real Paycheck

Impact💰💰💰💰💰

Why People Make This Mistake

You've been eating ramen for four years. Now you have a salary. Your brain screams: 'You deserve this!' And suddenly you need a nice apartment, new wardrobe, and weekend brunches that cost more than your college textbooks.

💸 The Real Cost

Spending an extra $1,000/month in your 20s instead of investing it costs you roughly $3.2 million by retirement (40 years at 10% returns). Every dollar of lifestyle inflation in your 20s is the most expensive dollar you'll ever spend.

✅ The Fix

Live like a college student for 2-3 more years after graduating. Bank the difference. You won't miss the fancy apartment — but you'll absolutely miss the $3M when you're 65.

🎯 Glen's Take

“When I landed my first real job, I kept my college-era spending habits for about two years. My friends thought I was cheap. Now those same friends ask me for financial advice. Funny how that works.”

#4Only Saving in a Savings Account

Impact💰💰💰💰💰

Why People Make This Mistake

It feels safe. The number only goes up. Your parents probably told you to 'save money,' and a savings account is literally called a savings account. But at 0.5% APY and 3% inflation, you're losing purchasing power every single year.

💸 The Real Cost

$10,000 sitting in a savings account for 30 years at 0.5% becomes $11,614. That same $10,000 in an S&P 500 index fund at 10% becomes $174,494. You're losing $162,880 by playing it 'safe.' Safety is the most dangerous financial strategy for young people.

✅ The Fix

Keep 3-6 months expenses in a high-yield savings account (4-5% APY). Everything beyond that goes into low-cost index funds. You have decades to ride out market dips.

🎯 Glen's Take

“The S&P 500 has never delivered negative returns over any 20-year period in its history. Not during the Depression. Not during 2008. Not during COVID. 'Safe' savings accounts are the riskiest thing a young person can own — you're guaranteed to lose to inflation.”

#5Ignoring Your Employer's 401K Match

Impact💰💰💰💰💰

Why People Make This Mistake

The enrollment forms are confusing. The fund options are overwhelming. You think you'll 'figure it out later.' Meanwhile, your employer is literally offering you free money and you're saying 'no thanks.'

💸 The Real Cost

A typical 50% match up to 6% of salary means if you earn $60K and contribute 6% ($3,600), your employer adds $1,800/year for free. Over 40 years at 10% returns, that free $1,800/year becomes $948,000. You just left nearly a million dollars on the table.

✅ The Fix

Log into your benefits portal right now and contribute at least enough to get the full employer match. It's an instant 50-100% return on your money. No investment in history beats free money.

🎯 Glen's Take

“I have met smart, educated people who leave their 401K match on the table for years because the paperwork seemed annoying. An hour of paperwork for a million dollars. That's the highest hourly rate you'll ever earn.”

#6Credit Card Debt Spiral

Impact💰💰💰💰💰

Why People Make This Mistake

Credit cards feel like free money when you're 23. You swipe, you get things, and the bill is 'future you's' problem. Then 22% APR interest starts compounding against you — the same compounding that builds wealth, now destroying it.

💸 The Real Cost

$5,000 in credit card debt at 22% APR, paying only minimums ($100/month), takes 9 years to pay off and costs $5,840 in interest alone. You end up paying $10,840 for $5,000 worth of stuff you probably don't even own anymore.

✅ The Fix

Pay off the highest-interest card first (avalanche method). Cut up all but one card for emergencies. If you can't buy it twice with cash, you can't afford it once with credit.

🎯 Glen's Take

“Credit card debt is the anti-compound interest. While your investments grow at 10%, your debt grows at 22%. You're running uphill on a treadmill that's going downhill. Kill the debt first, then invest.”

#7No Emergency Fund

Impact💰💰💰💰💰

Why People Make This Mistake

When you're young and invincible, emergencies happen to other people. Then your car breaks down, you need dental work, or you lose your job — and suddenly you're funding emergencies with credit cards at 22% APR.

💸 The Real Cost

Without an emergency fund, a $2,000 car repair becomes $4,000+ on a credit card. One medical bill can trigger a debt spiral that takes years to escape. The average American emergency costs $1,000-$5,000 — and they happen about once a year.

✅ The Fix

Build a $1,000 'starter' emergency fund as fast as possible (sell stuff, pick up a side gig, cut one subscription). Then gradually build to 3-6 months of expenses in a high-yield savings account.

🎯 Glen's Take

“I kept an emergency fund even when I was running my hedge fund. Markets crash. Clients leave. Income stops. The emergency fund isn't just about money — it's about sleeping at night.”

#8FOMO Spending (Keeping Up With Friends)

Impact💰💰💰💰💰

Why People Make This Mistake

Your friends post vacations on Instagram. Your coworker just leased a BMW. Everyone seems to be living better than you. So you spend money you don't have to maintain an image that doesn't matter.

💸 The Real Cost

An extra $500/month on 'keeping up' in your 20s (dinners, trips, clothes) costs roughly $1.6M in lost compound growth by retirement. You're trading your future financial freedom for someone else's approval.

✅ The Fix

Unfollow financial triggers on social media. Find friends who are also building wealth. Remember: the people flexing the hardest are usually the most broke. True wealth is invisible.

🎯 Glen's Take

“Half the people driving luxury cars in your 20s are financing them at 7% APR and eating ramen to make the payments. The other half have rich parents. Neither group is your competition.”

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Your 30s

7 common mistakes · Ages 30-39

Your 30s are when life gets expensive: houses, weddings, kids, career pivots. Income is rising but so are responsibilities. The mistakes here are about losing financial discipline just as the stakes get higher.

#1Buying Too Much House

Impact💰💰💰💰💰

Why People Make This Mistake

A realtor tells you that you're 'approved' for a $500K mortgage. Your parents say real estate is 'always a good investment.' Instagram makes every home look like a dream. So you buy at the top of your budget and become house-poor for the next 30 years.

💸 The Real Cost

A $500K house at 7% interest costs $698,000 in interest alone over 30 years. Total: $1.2M for a $500K house. If you'd bought a $350K house instead, you'd save $280,000 in interest — enough to fund your entire retirement at 10% returns.

✅ The Fix

Keep your housing costs under 25% of take-home pay (not gross). Buy less house than you're approved for. The bank calculates what you can technically survive — not what lets you thrive.

🎯 Glen's Take

“Your house is not an investment. It's an expense that occasionally appreciates. The returns on residential real estate, adjusted for maintenance, taxes, insurance, and opportunity cost, are mediocre. Your brokerage account will almost always outperform your home equity.”

#2Not Increasing 401K Contributions With Raises

Impact💰💰💰💰💰

Why People Make This Mistake

You get a 10% raise and immediately envision better dinners and a nicer car. The 401K contribution stays at 6% — the same percentage you set at 24 when you were making half as much.

💸 The Real Cost

If you increase your 401K contribution by just 1% every time you get a raise, over a 30-year career you could end up with $500,000 to $1M more in retirement savings. The money you never see, you never miss.

✅ The Fix

Every time you get a raise, bump your 401K contribution by at least 1%. Many plans offer auto-escalation — turn it on. Your future self will be stunned at how painlessly rich you became.

🎯 Glen's Take

“The best financial strategy is to save money you never knew you had. Auto-escalation on your 401K is the closest thing to a financial cheat code. Your lifestyle adjusts to whatever is left.”

#3Neglecting Life and Disability Insurance

Impact💰💰💰💰💰

Why People Make This Mistake

You're 33 and healthy. Insurance feels like paying for something that will never happen. Plus, the process of getting a policy is annoying. So you skip it — gambling your family's entire financial future on continued good health.

💸 The Real Cost

A $1M term life policy for a healthy 30-year-old costs roughly $30-50/month. Without it, if the worst happens, your family faces mortgage payments, childcare costs, and daily expenses with zero income. The average funeral alone costs $9,000+.

✅ The Fix

Get a 20-30 year term life policy with 10-12x your annual income in coverage. Also get long-term disability insurance (your income is your most valuable asset). Do it now — premiums only go up with age.

🎯 Glen's Take

“If anyone depends on your income, life insurance isn't optional — it's a moral obligation. Disability insurance is arguably more important: you're far more likely to be disabled than to die young. Protect your ability to earn.”

#4Keeping Up With the Joneses (Cars, Vacations, Lifestyle)

Impact💰💰💰💰💰

Why People Make This Mistake

Your neighbors renovated their kitchen. Your college roommate just posted from Bali. Your coworker drives a Tesla. In your 30s, the pressure to 'look successful' intensifies because now you actually have the income to fake it.

💸 The Real Cost

Leasing a $50K car instead of buying a reliable $25K used car costs roughly $15,000-$20,000 more over 5 years. That extra cost, invested at 10% for 25 years, grows to $160,000+. Your car is the most expensive depreciating asset most people own.

✅ The Fix

Drive a reliable used car. Take one great vacation instead of three mediocre ones. Renovate when you need to, not when your neighbor does. Wealth is what you don't see — it's in brokerage accounts, not driveways.

🎯 Glen's Take

“Warren Buffett drives a $40,000 car and lives in the same house he bought in 1958 for $31,500. He's worth $130 billion. The correlation between visible spending and actual wealth is roughly zero.”

#5Not Diversifying Beyond One Company's Stock

Impact💰💰💰💰💰

Why People Make This Mistake

Your employer gives you stock options or an ESPP. The stock has been going up. You feel loyal. You think you 'know' the company. So 60% of your net worth ends up in one stock — the same company that also pays your salary.

💸 The Real Cost

Enron employees had 62% of their 401K in company stock. When Enron collapsed, they lost their jobs AND their retirement savings simultaneously. This has happened at WorldCom, Lehman Brothers, and dozens of other companies.

✅ The Fix

Never hold more than 10% of your portfolio in any single stock — especially your employer's. Sell RSUs as they vest and diversify into index funds. Your career risk and investment risk should never be concentrated in the same company.

🎯 Glen's Take

“I ran a concentrated hedge fund, so I understand the temptation. But I was a professional stock picker with a full-time research operation. Even then, I diversified my personal savings across index funds. Concentration builds wealth; diversification preserves it.”

#6Ignoring Tax-Advantaged Accounts

Impact💰💰💰💰💰

Why People Make This Mistake

Roth IRAs, HSAs, backdoor Roths, 529 plans — the alphabet soup of tax-advantaged accounts is confusing. So you just use a regular brokerage account and pay full taxes on every dollar of gains.

💸 The Real Cost

Investing $6,500/year in a Roth IRA from age 30-60 at 10% returns gives you $1.18M completely tax-free. In a taxable account, you'd owe roughly $180,000-$280,000 in capital gains taxes. That's a quarter million dollars the IRS takes because you couldn't be bothered to open a different account type.

✅ The Fix

Priority order: (1) 401K up to employer match, (2) max out Roth IRA or backdoor Roth, (3) HSA if eligible (triple tax advantage), (4) max out remaining 401K, (5) taxable brokerage. Every dollar in the wrong account is taxed unnecessarily.

🎯 Glen's Take

“The tax code rewards people who read the instructions. Every tax-advantaged dollar is worth 20-37% more than a taxable dollar over your lifetime. It's the most reliable 'return' in investing — and it requires zero stock-picking skill.”

#7Having No Estate Plan When You Have Kids

Impact💰💰💰💰💰

Why People Make This Mistake

Estate planning sounds like something for old rich people. You're 35 with a toddler. But if you and your spouse die without a will, a judge decides who raises your children. A stranger in a courtroom, not you.

💸 The Real Cost

A basic will and trust costs $500-$2,000 with an attorney. Without one, probate can cost 3-7% of your estate, take 12-18 months, and create family conflicts that last generations. More importantly, your kids could end up with someone you'd never have chosen.

✅ The Fix

Get a will, designate guardians for your kids, set up beneficiaries on all accounts, and create a simple trust if your net worth exceeds $500K. Update it every 3-5 years or after major life events.

🎯 Glen's Take

“This one isn't about money — it's about your kids. Spend one Saturday getting a basic estate plan done. You'll feel a weight lift off your shoulders that you didn't even know was there.”

📈

Your 40s

6 common mistakes · Ages 40-49

Your 40s are peak earning years but also peak temptation years. You're likely at the height of your career, your kids are expensive, and the finish line of retirement starts to feel real. The mistakes here can derail decades of progress.

#1Funding Kids' College Over Your Own Retirement

Impact💰💰💰💰💰

Why People Make This Mistake

You love your kids. You don't want them drowning in student loans. So you drain your retirement savings to pay for their education — a noble gesture that quietly destroys your financial independence.

💸 The Real Cost

Pulling $100,000 from retirement at age 45 to pay for college costs you roughly $672,000 by age 65 (at 10% returns). Your kids can get scholarships, work part-time, or take student loans at 5-7%. You cannot get a loan for retirement.

✅ The Fix

Secure your own retirement first, then help with college. There are loans for education. There are no loans for retirement. Tell your kids: 'The best gift I can give you is not being a financial burden when I'm 75.'

🎯 Glen's Take

“Put on your own oxygen mask first. A parent who retires broke becomes a financial burden on the very children they sacrificed for. Fund your 401K, then help with college. Your kids will understand this when they're 40.”

#2Not Catching Up on Retirement Contributions

Impact💰💰💰💰💰

Why People Make This Mistake

You spent your 20s and 30s building a career and raising kids. Retirement savings took a back seat. Now you're 42, you're earning good money, but you're still contributing the same percentage you set a decade ago.

💸 The Real Cost

If you're behind on retirement at 40, every year you delay catching up costs exponentially more. An extra $500/month invested from 40-65 at 10% becomes $664,000. From 45-65, only $382,000. Five years of procrastination costs $282,000.

✅ The Fix

Max out your 401K ($23,500 in 2026). If you're 50+, add the $7,500 catch-up contribution. Open a Roth IRA. Use a spousal IRA if your partner doesn't work. Throw everything you can at retirement — the window is narrowing.

🎯 Glen's Take

“Your 40s are the last decade where time is meaningfully on your side. Every dollar invested here still has 20-25 years to compound. After 50, you're in catch-up mode. Don't waste the most powerful earning decade of your career.”

#3Mid-Life Crisis Purchases

Impact💰💰💰💰💰

Why People Make This Mistake

You're 45, you've been responsible for two decades, and you start wondering 'is this all there is?' So you buy a $70,000 sports car, a $30,000 watch, or a boat (a hole in the water you throw money into). It feels like freedom. It's actually a financial prison.

💸 The Real Cost

A $70,000 sports car financed at 6% over 5 years costs $81,200 total. That $70,000 invested instead would grow to $470,000 by age 65. The car will be worth $25,000 in five years. The investment would be worth nearly half a million.

✅ The Fix

If you need a thrill, find one that doesn't cost $70K. Travel, learn a new skill, start a business. If you absolutely must buy the toy, pay cash and cap it at 5% of your net worth. Never finance a depreciating asset for an emotional reason.

🎯 Glen's Take

“I've seen hedge fund managers blow six figures on watches while their 401K was underfunded. The mid-life crisis purchase is the adult version of FOMO spending in your 20s — same psychology, bigger price tag.”

#4Co-Signing Loans

Impact💰💰💰💰💰

Why People Make This Mistake

Your kid, sibling, or friend can't qualify for a loan on their own. They ask you to co-sign. You feel obligated. But co-signing means you're 100% responsible for the debt if they default — and statistically, about 40% of co-signers end up paying.

💸 The Real Cost

Co-signing a $30,000 car loan or $50,000 student loan that goes into default destroys your credit score (dropping 100+ points), triggers collection calls, and can lead to wage garnishment. Plus you lose the relationship anyway.

✅ The Fix

Just say no. If someone can't qualify for a loan on their own, the bank — whose entire job is assessing risk — has determined they're a bad bet. You're not smarter than the bank. If you want to help, gift a smaller amount you can afford to lose.

🎯 Glen's Take

“The fastest way to lose both money and a relationship is to co-sign a loan. If they default, you lose the money. If you try to collect, you lose the relationship. There's no winning scenario here.”

#5Not Rebalancing Your Portfolio

Impact💰💰💰💰💰

Why People Make This Mistake

You set your portfolio to 80/20 stocks/bonds at 30 and never touched it. After a decade-long bull market, you're now 95/5 — way too aggressive for someone nearing retirement. Or worse, you panicked during a crash and went 30/70 — way too conservative for someone who needs growth.

💸 The Real Cost

An over-aggressive portfolio can lose 40-50% in a crash right before retirement, forcing you to work an extra 5-10 years. An over-conservative portfolio might underperform by 2-3% annually, costing hundreds of thousands over 20 years.

✅ The Fix

Rebalance once a year, or use a target-date fund that does it automatically. A simple rule: subtract your age from 110 — that's your stock percentage. At 45, that's 65% stocks, 35% bonds.

🎯 Glen's Take

“Rebalancing is counterintuitive — you're selling winners and buying losers. But that's exactly what keeps your risk in line with your timeline. It's not exciting. It's not supposed to be. It's supposed to keep you solvent.”

#6Ignoring Healthcare Costs

Impact💰💰💰💰💰

Why People Make This Mistake

In your 40s, you start needing actual medical care. But you skip the HSA, choose the cheapest plan without reading the deductible, and assume your employer coverage will always be there.

💸 The Real Cost

The average American spends $315,000 on healthcare in retirement (Fidelity estimate). Without an HSA — the only account with triple tax advantages (deductible, tax-free growth, tax-free withdrawals for medical) — you're paying for all of this with after-tax dollars.

✅ The Fix

If eligible, max out your HSA ($4,150 individual, $8,300 family in 2026). Don't spend it — invest it and let it grow. Use it as a stealth retirement account for medical expenses. This is the most tax-advantaged account in the entire tax code.

🎯 Glen's Take

“The HSA is the Swiss Army knife of financial accounts: tax-deductible contributions, tax-free growth, and tax-free withdrawals for medical expenses. After 65, you can withdraw for any purpose (taxed like a 401K). It's an IRA with a bonus feature.”

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🎯

Your 50s

5 common mistakes · Ages 50-59

Your 50s are the final stretch before retirement. You can see the finish line, but you can also see the gap between where you are and where you need to be. The mistakes here are about panic, denial, and misguided generosity.

#1Not Taking Advantage of Catch-Up Contributions

Impact💰💰💰💰💰

Why People Make This Mistake

You turned 50 and nothing changed. You're still contributing the same amount to your 401K as you did at 40. The IRS literally gives you a bonus contribution limit after 50 — and you're leaving it unused.

💸 The Real Cost

The catch-up contribution is $7,500/year for 401K (total limit: $31,000). If you max this from 50-65 at 10% returns, the catch-up portion alone grows to $238,000+. Add the Roth IRA catch-up ($1,000 extra) and you're looking at even more.

✅ The Fix

The day you turn 50, increase your 401K contribution to the maximum allowed. If your budget can't handle it, find expenses to cut. These are the last 15 years where compounding can meaningfully work for you.

🎯 Glen's Take

“Catch-up contributions exist because Congress knows most Americans are behind on retirement savings. It's a lifeline. Grab it with both hands. Cut the cable, sell the second car, eat at home — whatever it takes to max these out.”

#2Planning to Take Social Security Too Early

Impact💰💰💰💰💰

Why People Make This Mistake

You're eligible at 62 and you want the money now. Your coworker took it early and seems fine. What you don't realize is that taking Social Security at 62 vs. 70 means permanently smaller checks for the rest of your life.

💸 The Real Cost

Social Security increases about 8% for every year you delay between 62 and 70. If your benefit at 62 is $2,000/month, it's $3,520/month at 70. Over a 20-year retirement, that's $365,000 more in total benefits. For married couples, the math is even more dramatic.

✅ The Fix

If you're healthy and can afford to wait, delay Social Security until at least your full retirement age (67) or ideally 70. Use other savings to bridge the gap. It's the best guaranteed 8% annual return you'll ever find.

🎯 Glen's Take

“Social Security is longevity insurance. The longer you live, the more valuable delayed benefits become. If you live to 85 (which is increasingly likely), taking benefits at 70 instead of 62 could mean $400,000+ more in lifetime income.”

#3Not Having a Withdrawal Strategy

Impact💰💰💰💰💰

Why People Make This Mistake

You spent 30 years learning how to save and invest. But nobody teaches you how to take money out. Most people enter retirement with no plan for which accounts to draw from, in what order, or at what rate.

💸 The Real Cost

The wrong withdrawal order can cost $100,000+ in unnecessary taxes over a retirement. Pulling too much too early can deplete your portfolio decades before you die. The 'wrong' 4% rule application during a bad market sequence can cut your portfolio in half.

✅ The Fix

Develop a tax-efficient withdrawal strategy: draw from taxable accounts first (lowest tax), then tax-deferred (401K/IRA), then tax-free (Roth) last. Consider Roth conversions in low-income years. The 4% rule is a starting point, not a commandment.

🎯 Glen's Take

“Accumulation is simple: put money in, let it grow. Decumulation is a chess game. Which accounts, in what order, at what rate, considering taxes, Social Security timing, and market conditions. Get a fee-only financial planner for this phase.”

#4Underestimating Healthcare Costs in Retirement

Impact💰💰💰💰💰

Why People Make This Mistake

You assume Medicare covers everything. It doesn't. Medicare doesn't cover dental, vision, hearing, most long-term care, or many prescription drugs without supplemental plans. The out-of-pocket costs are staggering.

💸 The Real Cost

A 65-year-old couple retiring today needs approximately $315,000 saved just for healthcare in retirement (Fidelity, 2025). Long-term care adds another potential $100,000-$400,000. Medicare premiums alone are $175+/month per person, and they go up with income.

✅ The Fix

Factor healthcare into your retirement number explicitly. Budget $6,000-$10,000/year per person for Medicare premiums and out-of-pocket costs. Consider long-term care insurance in your late 50s (premiums skyrocket after 60). Build your HSA now.

🎯 Glen's Take

“Healthcare is the silent retirement killer. I've seen people with 'enough' saved for retirement discover they didn't account for $600,000+ in medical expenses over 25 years. Run the numbers with healthcare included, not as an afterthought.”

#5Helping Adult Children at the Expense of Retirement

Impact💰💰💰💰💰

Why People Make This Mistake

Your adult kids are struggling — student loans, high rent, job instability. You love them, so you help. $500 here for rent, $1,000 there for a car repair. Gradually, you're funding two households on one retirement timeline.

💸 The Real Cost

Giving adult children $1,000/month from age 55-65 costs you $120,000 in direct gifts plus roughly $200,000 in lost investment returns. That's $320,000 less in your retirement accounts — potentially the difference between independence and dependence.

✅ The Fix

Set clear boundaries: 'I can help with X, but my retirement savings are non-negotiable.' Help your kids build skills and income, not dependency. The best long-term help is teaching financial independence, not subsidizing its absence.

🎯 Glen's Take

“This one's hard. Nobody wants to say no to their kids. But every dollar you give your 28-year-old today is a dollar you might desperately need at 78. Help them learn to fish. Don't sell your fishing boat to buy them dinner.”

🏖️

Your 60s+

4 common mistakes · Ages 60+

You're in or near retirement. The focus shifts from growth to preservation, income, and making your money last potentially 30+ more years. The mistakes here can't be fixed by earning more — there's no going back.

#1Being Too Conservative (Longevity Risk)

Impact💰💰💰💰💰

Why People Make This Mistake

You just retired and you're terrified of losing money. So you move everything to bonds and CDs. It feels safe. But if you live to 90 — which is increasingly likely — your money needs to last 25-30 years. An all-bond portfolio can't do that.

💸 The Real Cost

A 100% bond portfolio earning 4% will be devastated by inflation over 25 years. $1 million at 4% with 3% inflation loses half its purchasing power in 25 years. Meanwhile, a balanced 50/50 portfolio historically preserves purchasing power indefinitely.

✅ The Fix

Keep at least 40-60% in stocks even in retirement. Yes, stocks are volatile short-term. But you're not spending your entire portfolio this year — most of it won't be touched for 10-20 years. That's plenty of time for stocks to recover and grow.

🎯 Glen's Take

“The biggest risk in retirement isn't a market crash — it's running out of money at 85 because you were 'playing it safe' for 20 years. Inflation is the silent killer of conservative portfolios. You need stocks to beat it.”

#2Not Planning for Inflation in Retirement

Impact💰💰💰💰💰

Why People Make This Mistake

You calculated that you need $60,000/year in retirement. But you didn't account for the fact that $60,000 in 2026 dollars will feel like $33,000 in 2046 at 3% inflation. Your expenses don't stay flat — they grow every single year.

💸 The Real Cost

At 3% average inflation, your costs double every 24 years. A retiree who needs $5,000/month at 65 will need $10,000/month at 89 for the same lifestyle. Most retirees who 'run out of money' didn't overspend — they under-planned for inflation.

✅ The Fix

Build a 3% annual inflation increase into your retirement plan. Invest a portion of your portfolio in assets that historically beat inflation: stocks, TIPS (Treasury Inflation-Protected Securities), and real estate. Your retirement plan should be inflation-adjusted, not nominal.

🎯 Glen's Take

“When I build financial models, I always run them in real (inflation-adjusted) dollars. A retirement plan that looks great in nominal terms can be a disaster in real terms. If your plan doesn't account for inflation, you don't have a plan.”

#3Ignoring Required Minimum Distributions (RMDs)

Impact💰💰💰💰💰

Why People Make This Mistake

You hit 73 (the current RMD age) and don't realize the IRS now requires you to withdraw from your traditional IRA and 401K every year. Miss an RMD and the penalty is 25% of the amount you should have withdrawn. Forget entirely and you could owe tens of thousands.

💸 The Real Cost

Missing a $40,000 RMD triggers a $10,000 penalty (25%). But the bigger cost is poor planning: if you've been deferring taxes for 40 years, your RMDs can push you into a much higher tax bracket, costing thousands per year in unnecessary taxes.

✅ The Fix

Start planning for RMDs in your late 50s and 60s. Consider Roth conversions during low-income years (between retirement and age 73) to reduce future RMDs. Set up automatic RMD withdrawals with your custodian so you never miss one.

🎯 Glen's Take

“RMDs are the government's way of finally collecting the taxes you deferred for decades. Smart retirees do Roth conversions in their 60s to reduce the RMD tax bomb. It's one of the biggest tax-planning opportunities in retirement — and most people miss it entirely.”

#4No Tax-Efficient Withdrawal Plan

Impact💰💰💰💰💰

Why People Make This Mistake

You have a traditional 401K, a Roth IRA, a taxable brokerage, and Social Security. Most retirees just pull from whatever account is convenient. But the order you draw from these accounts can cost or save you hundreds of thousands in taxes over 20+ years.

💸 The Real Cost

Poor withdrawal sequencing can mean paying 22-32% tax rates when you could be paying 10-12% by drawing strategically. Over a 25-year retirement with $80,000/year in withdrawals, the wrong order could cost $200,000-$400,000 in unnecessary taxes.

✅ The Fix

General strategy: draw from taxable accounts first (capital gains rates are lower), then tax-deferred (401K/IRA) to fill up lower tax brackets, then Roth IRA last (tax-free growth continues). Do Roth conversions in low-income years between retirement and 73.

🎯 Glen's Take

“Tax planning in retirement is a second career in itself. The difference between a smart withdrawal strategy and a naive one can fund five extra years of retirement. This is where a fee-only fiduciary financial advisor earns their fee many times over.”

The Pattern Behind Every Mistake

If you read all 30 mistakes above, you'll notice they all share the same DNA. Every single money mistake is a version of one of three things:

Short-Term Thinking

Choosing comfort now over wealth later. FOMO spending, lifestyle inflation, mid-life crisis purchases — they all trade decades of compounding for a dopamine hit.

Fear of Action

Not investing, not negotiating, not getting insurance, not estate planning. The cost of inaction almost always exceeds the cost of imperfect action.

Ignoring Math

Buying too much house, taking Social Security early, being too conservative in retirement. The math is available. Most people just don't run the numbers.

The antidote to all three? Automate everything. Automatic 401K contributions, automatic investments, automatic rebalancing. Remove yourself from the equation, because your brain's default settings are optimized for survival on the savanna — not for building a retirement portfolio.

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Frequently Asked Questions

What is the single biggest money mistake people make?+

Not investing early enough. The math is brutal: every decade you delay investing roughly cuts your final wealth in half. Someone who invests $200/month from 22 to 62 at 10% returns accumulates over $1.2 million. Start at 32 and that drops to $456,000. Start at 42 and it's $152,000. Time is the most powerful force in finance, and you can never get it back.

What money mistakes do most people in their 20s make?+

The most damaging mistakes in your 20s are: not starting to invest immediately (losing decades of compound growth), not negotiating your first salary (which costs $600K+ over a career), lifestyle inflation with your first paycheck, ignoring your employer's 401K match (leaving free money on the table), and credit card debt spirals. The common thread is short-term thinking — your 20s feel infinite but they're the most financially powerful decade of your life.

Is it too late to fix my finances at 40 or 50?+

Absolutely not, but the math gets harder. At 40, you still have 25 years of compounding ahead. At 50, you have 15 years plus catch-up contributions ($7,500 extra per year in your 401K). The key is to act with urgency: max out tax-advantaged accounts, slash unnecessary spending, and stop making the big-ticket mistakes (too much house, co-signing loans, funding kids' college before your own retirement). Many people build the majority of their wealth between 45 and 65 as their income peaks.

How much should I have saved for retirement at each age?+

A widely used benchmark: by 30, have 1x your annual salary saved; by 40, 3x; by 50, 6x; by 60, 8x; by 67, 10x. So if you earn $80,000, you'd target $80K saved by 30, $240K by 40, $480K by 50, $640K by 60, and $800K by 67. These are rough targets — your actual number depends on your desired retirement lifestyle, Social Security benefits, healthcare costs, and expected investment returns.

Should I pay off debt or invest first?+

It depends on the interest rate. Pay off any debt above 7-8% first (credit cards, personal loans) — no investment reliably returns 22% per year. For debt below 5% (most mortgages, federal student loans), invest simultaneously because your investment returns will likely exceed the interest cost. For debt between 5-8%, do both: pay minimums on the debt and invest the rest. Always capture your full employer 401K match regardless of debt — that's a guaranteed 50-100% return.

What's the most underrated financial account?+

The Health Savings Account (HSA). It's the only account in the US tax code with triple tax advantages: contributions are tax-deductible, growth is tax-free, and withdrawals for medical expenses are tax-free. After age 65, you can withdraw for any purpose (taxed like a regular IRA). Most people use their HSA like a checking account for medical bills. Instead, pay medical costs out of pocket, invest your HSA contributions in index funds, and let it grow tax-free for decades. A fully invested HSA can accumulate $500,000+ by retirement.

What money mistakes should I absolutely avoid in a recession?+

The three most destructive recession mistakes are: (1) panic-selling your investments at the bottom (locking in losses permanently), (2) stopping your regular investment contributions (missing the recovery, which is where most returns happen), and (3) raiding your retirement accounts (triggering taxes, penalties, and permanently reducing your compounding base). Recessions are when wealth is transferred from the impatient to the patient. Keep investing, keep your emergency fund intact, and wait it out.

Recommended Resources

Tools & books I actually use and recommend

The Psychology of Money

Morgan Housel on why managing money is about behavior, not intelligence. Short, brilliant chapters you'll re-read.

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The Little Book of Common Sense Investing

John Bogle's manifesto on why low-cost index funds beat everything else. Straight from the founder of Vanguard.

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TradingView

Best charting platform out there. Real-time data, screeners, and a community of millions of traders.

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