Why do you always fail to hold onto big gains but can withstand huge losses

Last night, the CPI data was released, with a year-over-year increase of 3.8% in April, reaching a new high since 2023.
The Nasdaq, Qualcomm, Intel, Micron... all declined, and some people said this wave was over.
As a result, within less than 24 hours today, it basically rebounded.
The University of Chicago studied account records of a group of active traders, and one common feature among the most severely losing group: the average holding time for losing positions is 2.4 times longer than for profitable positions.
Profitable trades are closed on average after 17 days, while losing trades are held for an average of 42 days before admitting defeat.
This is not a matter of personal character, but just the default setting of the human brain.
Psychologically, it’s called loss aversion—the pain of losing 100 yuan is twice the pleasure of earning 100 yuan.
So when making profits, the brain desperately wants to lock in gains; when losing, the brain desperately wants to break even.
The result is: the opportunities the market gives you, you only take a bite and run; the lessons the market teaches you, you stubbornly hold on and don’t learn.
This time, the CPI exceeded expectations, and the reasons for the decline—Nvidia’s orders, AI server demand, the tight supply of storage chips—these haven’t changed.
The decline was driven by emotion.
If you had sold last night, the cost to buy back today would be higher than the selling price, plus transaction fees.
The more trades you make, the higher the friction costs, the greater the emotional toll, and the harder it is for your account to grow.
The hardest part isn’t stock picking; it’s when the market has noise, whether you can identify your choices and avoid reckless operations.