German investors who bought the right global ETF still managed to lose about 1.69% every year, not to a crash and not to the market, but to themselves. Spread across 30 years of investing 500 euros a month, that gap turns roughly 487,000 euros of simple buy-and-hold wealth into about 361,000 euros. Same market, same fund, 126,000 euros gone. The most expensive thing in your portfolio is not fees or a bear market. It is the urge to keep doing something.
Where does the money actually leak?
The numbers above come from research on real German ETF investors, summarized by justETF. When their results were compared with a plain buy-and-hold position in a global MSCI World index, the average investor gave up 1.69% per year, split into two habits: 1.28% lost picking the wrong ETFs, and 0.41% lost to timing. Notice what is missing: the market. The index did its job. The investors subtracted from it.
Isn’t picking the winners the whole point?
Nobel laureate William Sharpe showed a simple truth: as a group, active investors must underperform the market after their higher costs, because together they are the market. Per S&P’s SPIVA scorecard, 65% of large-cap active funds underperformed the S&P 500 in 2024, and over the 15 years ending December 2024, no category of professional managers had a majority beat its benchmark. Own the market instead of fighting it.
How fast does slow actually compound?
Use the Rule of 72: divide 72 by your yearly return to see how long money takes to double. At the MSCI World’s historical 7.5%, that is about 9.5 years. Adjusted for inflation, equities (4.5% real) double in 16 years, government bonds (1%) in 72 years, and cash (0.5%) in 144 years. In reverse, at 2% inflation cash loses half its value in about 36 years. Doing nothing risky is its own risk.
The one cost you fully control
A 2% annual fee halves your money in about 36 years before any market moves; a 0.2% ETF fee takes 360 years to do the same damage. In one justETF example, the gap between a 0.14% index ETF and a 1.8% active fund came to over 23,000 pounds in costs over 15 years on a 50,000 pound investment.
What if you are just starting?
Make the boring choice automatic: a monthly savings plan into a broad, low-cost global tracker (MSCI World or FTSE All-World), fixed amount, taken before you can spend it. Then leave it alone. Automation is the defense against the 1.69% you would otherwise lose to your own decisions.
What if you already invest?
Your biggest risk is you. The German data is about people who already owned the right tools and undermined them. justETF calls panic-selling the biggest mistake of all, because it locks in losses and leaves you out of the recovery. Doing nothing during turbulence is a real skill.
The uncomfortable part
Slow investing works precisely because it is dull and hard to stick with. Its edge is behavioral, not clever, and no version pays out next quarter. What it offers is a high probability of a good outcome for people who can sit still for years. That is the opposite of what get-rich-quick sells, and why the patient version keeps quietly winning.
This article is general educational information, not personalized financial, investment, or tax advice. Investments can lose value, and past performance is not indicative of future results. Consider your own circumstances or speak with a licensed professional before making decisions.
Sources: justETF Academy: Why do ETF investors fail?, 6 biggest mistakes ETF investors make, Rule of 72; S&P SPIVA U.S. Year-End 2024.