Overconfidence and overtrading: the most expensive bias

We are, on average, far more confident than we are correct. In trading, that gap has a price tag.

The evidence

Brad Barber and Terrance Odean's research connects the dots cleanly: overconfident investors trade more, and the more they trade, the worse they do. In their well-known study Boys Will Be Boys, the group that displayed more overconfidence traded more actively — and earned lower net returns as a direct result.

Net annual return by trading activity

The mechanism isn't subtle. Overconfidence convinces you that you know more than the price already reflects, so you act more often. Every action carries costs, and many of the actions are the emotional trades that erode returns.

Why it's so hard to see in yourself

Overconfidence is invisible from the inside — by definition, it feels like accurate judgment. A winning streak feels like skill; a good call feels like proof of more good calls to come. None of that registers as a bias while it's happening.

Restraint you don't have to summon

Since you can't reliably feel the bias, the answer is a system that doesn't share it. A rules-based process only acts when your predefined conditions are met, which caps how often overconfidence can express itself. It can't be talked into "just one more trade" because it has no feelings to flatter.

The uncomfortable but liberating takeaway: for most individuals, the path to better results runs through fewer, more disciplined trades — not more clever ones.

---

This article is educational and does not constitute investment advice or a recommendation. Options trading involves substantial risk and is not suitable for every investor. Autopilot Options does not guarantee profits or prevent losses. Past performance and historical data do not guarantee future results.