Self-serving bias
Taking credit for success and attributing failure to circumstances, other people or luck. Your wins are you; your losses are the market.
What drives it
Protects self-esteem and keeps motivation up after setbacks. A mild version is normal and goes with good mental health; its absence is associated with depression.
How it shows
Work
Post-mortems where the leader's account of the win features their decisions and the account of the loss features the board, the economy and the sales team. 'We hit target because of the strategy; we missed because execution let us down.' Ask each team member for their share of the credit and the total runs well over the whole. When judging others it runs in reverse: a rival's success is luck or connections, their failure is who they are.
Relationships
Each partner overestimates their share of the housework (Ross and Sicoly found joint estimates exceed the whole). Rows in which every bad outcome traces back to the other person's choice. 'I only shouted because you...'
Self
Compare the story you tell after a good result with the one after a bad result and notice whether the agent changes. When identifying patterns in others, catch the mirror image: reaching for luck when a rival wins and for bad timing when a friend fails.
What tells it apart
Self-enhancement: Self-enhancement is the broader motive and shows in global self-ratings ('I'm above average'); self-serving bias is specifically visible in how the explanation switches between success and failure.
Fundamental attribution error: The attribution error is about interpreting other people's behaviour as character; self-serving bias is about your own outcomes and flips with whether the result was good or bad for you.
Rationalisation: Rationalisation builds a detailed, plausible justification for a specific act after the fact; self-serving bias is the simple directional switch of credit and blame, visible even in one-line explanations.
A test
Compare how the person explains comparable successes and failures; if agency appears only on the winning side, the bias may be operating, and if they own failures specifically and credit others for wins, it is not.
Questions to carry
- How do the stories of the last win and the last loss compare, and who gets the credit in each?
- When something of mine went badly, which outside causes came to mind first, and which of my choices went unmentioned?
How strong the research is
strong
Where it comes from
Dale Miller and Michael Ross, 1975; Amy Mezulis and colleagues, 2004 (meta-analysis)