Post-purchase Rationalization
Choice-Supportive Bias
A cognitive bias describing a tendency to retroactively ascribe positive attributes to an option one has selected — for example, in assigning positive values to a purchase that was recently made.
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Origin
Mara Mather, Eldar Shafir, and Marcia K. Johnson named and documented the bias in a 2000 paper in Psychological Science, showing that participants misremembered more positive features for chosen options and more negative ones for rejected options — a distortion at the point of memory retrieval, not the original decision. The work built on Leon Festinger's 1957 cognitive dissonance theory and Jack Brehm's 1956 experiments showing people rated chosen appliances more favourably after selecting them.
Updated February 22, 2026