Psychologie a chování
Disposition Effect: Why We Hold Losers and Sell Winners
Key takeaways
- The disposition effect is the tendency to sell winners too soon and hold losers too long.
- It is driven by the desire to lock in a gain (good feeling) and the avoidance of realising a loss (painful feeling).
- The optimal strategy is the reverse: let winners run and reassess losing positions objectively.
- Tax optimisation can counteract the disposition effect — in certain situations it pays to deliberately realise a loss.
The disposition effect is the tendency of investors to sell profitable stocks too soon and, conversely, to hold losing positions too long — in the hope that they will return to the purchase price. It was described by Hersh Shefrin and Meir Statman in 1985, but it continues to affect the vast majority of individual investors today.
Why we do it
The roots lie in Kahneman and Tversky's prospect theory: the value of a gain and a loss is not symmetric. Realising a gain delivers an immediate good feeling. Realising a loss is painful — and so we avoid it. Instead, we tell ourselves: "I'll wait until it comes back." But the market does not know your purchase price and does not care about it.
How the disposition effect harms returns
An investor who follows the disposition effect systematically sells the strongest positions (where the potential for further growth is greatest) and holds the weakest (where the fundamentals are worst). This runs directly counter to the purpose of a well-diversified portfolio, where the goal is to maintain allocation — not to react to paper gains or losses.
How to defend against it
- Evaluate each position from scratch. Ask: "Would I buy this today at the current price?" Not: "Am I in profit or at a loss?"
- Set rebalancing rules — portfolio moves are then driven by logic, not emotions.
- Deliberate loss realisation as part of tax optimisation can overcome the disposition effect: in some cases it is worth realising a loss because it reduces the tax liability.
The disposition effect and passive index investing
This effect is one more reason why a passive index strategy outperforms the average active investor. An index sells and buys automatically based on weight — without emotions, without purchase prices as anchors.
FAQ
What is the disposition effect?
The tendency to sell profitable stocks too soon and hold losing positions too long. It is caused by the asymmetry of emotions: realising a gain feels pleasant, realising a loss feels painful.
How does the disposition effect harm returns?
The investor sells the strongest positions and holds the weakest — exactly the opposite of optimal behaviour. This systematically strips the portfolio of its growth potential and retains assets with the worst fundamentals.
How do you overcome the disposition effect?
Evaluate each position regardless of the purchase price — ask whether you would buy it today. Set rebalancing rules and, when appropriate, deliberately realise losses for tax optimisation.