15 Investing Lessons We Wish We Knew at 18

Apr 18, 2025 6 min read

Patrick

“All the returns in life, whether in wealth, relationships, or knowledge, come from compound interest”

– Naval Ravikant, entrepreneur and investor

arvy’s teaser: We turn 33 this year. Here are 15 investing lessons we wish we knew at 18.

1. If you invest, you can lose. If you don’t invest, you’ve already lost.

Inflation is a silent killer. At just 2% per year, your CHF 100 today is worth CHF 54 in 30 years and CHF 36 in 50 years. Do nothing, and you guarantee loss. Investing is the only way to fight back.

Chart 1: What your CHF 100 will be worth after 50 years with an inflation rate of 2 or 3%

Source: arvy

2. Lump Sum + Dollar-Cost Averaging (DCA) is the holy grail of investing.

Start with a lump sum and invest 10% of your net salary every month, no matter what. Whether the market is up or down, consistency is your best friend. The power of compounding does the heavy lifting over time.

3. Compounding applies to everything in life, not just money.

As Naval Ravikant said, “All returns in life, whether in wealth, relationships, or knowledge, come from compound interest.” Build, iterate, and play long-term games with long-term people.

4. Thus, never stop learning. The single greatest investment in the world is in YOU.

Investing teaches you about markets, psychology, and yourself. Read books, follow great investors and people, and stay curious. Never think twice about investments in yourself. The more you learn, the better your decisions will be.

5. Volatility isn’t your enemy—it’s your opportunity.

Market dips of -10%, -20%, or even -30% aren’t signals to panic; they’re signals to buy more. In the long run, markets go up, and volatility evens out. Historically, the S&P 500 has returned around 10% per year before inflation.

Chart 2: Bear markets in the S&P 500 since 1950 and subsequent recoveries

Source: Personal Finance Club, S&P 500 log graph since 1950, showing all 15%+ drops

6. The stock market doubles your money every 10 years (on average).

The real return on equities (after inflation) has averaged 7% per year over the last 200+ years. That means your money roughly doubles every decade. Start early, and time becomes your superpower.

7. Don’t chase hot tips or the next big thing—it’s a shortcut to losing money.

I’ve done it. It hurt. A “sure thing” stock tip is usually neither sure nor a thing. And trying to find the next Amazon or Tesla is like playing the lottery. Most speculative investments fail. Stick to your investment plan and leave fast-money schemes to gamblers and scammers.

8. The stock market climbs the wall of worry.

Over the last 100 years, we’ve faced two world wars, 25 recessions, oil crises, pandemics, and financial meltdowns—yet the market has still grown at 7-10% per year. There’s always a reason to sell, but long-term investors win by tuning out the noise.

9. Investing is NOT gambling.

In 150+ years of stock market history, there has never been a single 20-year period where investors lost money. No matter when you invested, a long enough time horizon always led to gains—even after adjusting for inflation.

Chart 3: Total real market returns, 1871 – 2022

Source: Robert Shiller, S&P 500 Composite, Bloomberg

10. Leverage is the root of all evil.

Using margin (borrowing money to invest) might seem like an easy way to amplify gains, but it can also wipe you out completely. Avoid it. Period.

11. Don’t wait for the next crash to invest.

“I’ll invest when the market crashes again” sounds smart, but it’s deeply flawed. Market timing is nearly impossible. Those who wait often miss out on years of growth. Instead, invest steadily with dollar-cost averaging.

12. Reinvest your dividends.

Dividends feel nice, but spending them is a mistake. Reinvesting them significantly accelerates compounding. Over time, dividends can make up 40% of total stock market returns.

13. Never interrupt your dollar-cost averaging plan.

Stopping your investing plan because “the market is crashing” or because you “want to buy something else” is one of the costliest mistakes you can make. The key to wealth isn’t just investing—it’s sticking with it.

14. Master delayed gratification—Investing is a journey, not a sprint.

True wealth isn’t built overnight. The best investors think long-term, stay patient, and trust the process. The journey matters—every setback, every lesson, every market dip is part of the game. Play for decades, not weeks. Those who stay in the game win.

15. I wish I had started sooner. Time is your superpower.

CHF 500/month invested at 18 = CHF 200K by 33. The best time to invest was 15 years ago. The second-best time is today. Start now.

Chart 4: The power of compound interest