Reason-based choice
We decide by finding good reasons we can articulate, not by computing utilities.
What it means
Reason-based choice is the account that people often make decisions by seeking and constructing reasons that justify one option over another, rather than by weighing attributes into an overall value as classical utility theory assumes. On this view a choice is made when a compelling, defensible rationale emerges, so the decision can hinge on which features lend themselves to articulate justification and on the desire to avoid choices that would be hard to defend to oneself or others. The framework elegantly explains anomalies that utility maximization cannot: adding an inferior option can change which of the original options is chosen because it supplies a reason (the compromise and asymmetric-dominance effects), and providing a reason to choose either of two equally attractive options can paradoxically increase the tendency to defer or seek more options. It connects to accountability, anticipated regret, and the constructed nature of preferences. It matters because it implies preferences are assembled at the moment of choice from available reasons, making decisions malleable to how options and their rationales are framed.
Examples
Offered a choice between two attractive vacations, people often defer; given a single option with one clearly winning feature, they choose readily — the decisive reason, not the value, breaks the tie.
Shown a basic camera and a professional one, buyers dither; add a top-end model and the middle one sells, because 'it's the sensible compromise' is a reason you can say aloud.
A hiring panel picks the candidate whose strength is easiest to write in the memo — 'ran a team of twelve' — over the one whose promise is real but harder to justify.
First described in Shafir, Simonson & Tversky (1993).