Behavior: why trading back and forth empties your pockets

Transcript

If you bought an S&P 500 fund in June 2025 and simply held it, you were up about 31 percent by October 2026. If you missed only the ten best days in that time, just ten out of 346, you had barely 8 percent. I'm Peter. Today is not about stocks, it is about you: why trading back and forth empties your pockets, why the way you split your money comes first, and how the watchlist gives you rules instead of gut feeling.

And here is the nasty part. The best days almost never come in calm times. At the end of March 2026, the fund fell by almost two percent on two days in a row. Two trading days later came the best day of the whole period, plus 2.9 percent. In June, the same picture: minus 2.6 percent, a few days later plus 1.7. If you get out after the scare, you are usually not there for the recovery.

This is not a one-off. Researchers Barber and Odean studied the accounts of 66,465 households at a large US discount broker over six years. The average household turned over three quarters of its portfolio every year. And the fifth that traded the most earned 11.4 percent a year. The market made 17.9 in the same period. Their title says it all: trading is hazardous to your wealth.

So why do we keep doing it? The researchers point to one main reason: overconfidence. We believe we know what happens next. Add fear when prices fall and greed when everyone talks about one stock. Every buy and sell costs fees, often taxes, and above all the chance to be there on the best days.

Before you think about single stocks, there is a bigger question: how much of your money belongs in stocks at all, and how much in bonds or in your account? That is called asset allocation. Researchers Ibbotson and Kaplan showed in 2000 that how high a fund's return turns out on average depends almost entirely on this split. And it decides how deep you fall in the next crash. Choose it so that you can stay calm even then.

That is exactly why every stock in your watchlist has one of two states. "On track" means: everything is fine, let it run. Even a stock that has already risen a lot stays on track as long as its up-trend holds. "Review" only comes when two things happen together: it is priced above its fair value, and the trend has turned. Or when the quality of the company clearly declines.

Why like this? Because the two most common mistakes point in opposite directions. One sells winners too early, out of fear of losing the gain. The other holds losers too long, because nobody likes to be wrong. The rule lets winners run and only speaks up when something has really changed. And "Review" does not mean "sell". It means: take a look and decide on purpose. With Pro you get an email when one of your stocks turns, so you do not have to check every day.

In short: the best days live next to the worst, trading a lot costs return on average, the split of your money comes first, and rules protect you from yourself. In the next lesson, you set up your watchlist so these rules work for you. Important: this is not financial advice.