The mind treats ease of recall as evidence of frequency. One dramatic memory - a gap that blew through a stop, a friend who made a year of income on one trade - crowds out the hundreds of ordinary days that never made an impression.
Traders feel this after anything memorable. A single overnight gap makes every swing position feel reckless for a month. One screenshot of a huge winner circulating in a forum makes that outcome feel like the normal result of the strategy rather than its rare tail.
Counting beats recalling. If you want to know how often a setup gaps against you, go through the records and count. Your trading-journal exists precisely because memory is a biased sample of your own history.
Related: base-rate-neglect, narrative-fallacy, recency-bias