Action bias
Also known as: Bias for action, Do-something bias
The pull to do something rather than wait, even when waiting is better.
What it means
Action bias is the tendency to favor doing something over doing nothing, even when the action carries no expected benefit or a worse one than waiting. The mechanism is part psychological and part reputational: acting restores a felt sense of control and signals competence and effort, while standing still looks passive and invites blame if things go badly, so we intervene partly to be seen intervening. It shows up in goalkeepers diving at penalty kicks, doctors ordering tests and procedures of marginal value, investors trading through market noise, managers reorganizing teams, and legislators responding to every crisis. It is not always a bias — where situations move fast and moves are reversible, acting first is often correct — but it turns costly when the base rate favors patience, when the action is irreversible, or when its side effects exceed the original problem. It matters because most institutions reward visible action over quiet restraint, so the bias compounds instead of correcting.
Examples
Facing a penalty kick, goalkeepers almost always dive left or right, though staying centred stops more shots; diving feels like doing the job, while standing still looks like failing to try.
A patient's ordinary back pain gets an MRI, then a referral, then surgery, because at each step both doctor and patient find escalating easier to justify than watching and waiting.
An investor rattled by a market dip sells and rebuys through the noise, paying fees and taxes, while the colleague who did nothing quietly ends the year ahead.
First described in Patt & Zeckhauser (2000); Bar-Eli et al. (2007).