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FOMO: Watching A Move You Missed

The urge to chase a price move you didn't position for is one of the most reliable ways to turn a disciplined process into an impulsive one, because it substitutes regret about the past for a reasoned view about what happens next.

A stock rips 8% on news you saw coming but didn't trade, or a strategy signal fired and you sat it out, and now the position you didn't take is sitting on a gain you can picture as yours. The pull to chase it — buying after the move, sizing up a similar setup next time "to make up for it" — is FOMO, and it's dangerous specifically because it's driven by regret about a past decision rather than by any actual edge in the current price. The move having already happened is not evidence that it will continue; if anything, chasing a move after most of it has occurred means buying at a worse price with a smaller expected edge than the original entry would have offered.

The tell that FOMO rather than genuine analysis is driving a decision is the reasoning itself: "I should have been in this" is not a forecast, it's a feeling about the past, and a trade justified that way skips the normal step of asking what edge exists from here. A disciplined process asks the same question of every new trade regardless of what just happened — does the current setup, at the current price, meet the same bar every other trade has to clear — and a chased position rarely does, because its real justification is emotional closure, not expected value.

The standard discipline against it is mechanical: require every position to pass the same written entry criteria used for any other trade, and treat "I missed this one" as information about the process (why wasn't this on your radar earlier?) rather than a reason to act now.

FOMO substitutes regret about a missed move for an actual forecast about what happens next — the giveaway is a trade justified by "I should have been in this" rather than by the same entry criteria applied to any other trade, and it typically means buying in after the best of the edge has already gone.

Related concepts

Further reading

  • Steenbarger, The Daily Trading Coach
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