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Why We Overpay at Auctions

Tom Stafford discusses a lot of the psychological principles that make rational bidding hard. Auctions also hit on many psychological persuasion techniques:

First, auctions use the principle of scarcity, whereby we overvalue things that we think might run out. Auction items are scarce in that they are unique (only one person can have it), and scarce in time (after the bids are finished, you’ve lost your chance). Think how many shop sales successfully rely on scarcity heuristics such as “Last day of sale!”, or “Only 2 left in stock!”, and you’ll get a feel for how powerful this persuasion principle can be.

The other principle used by auctions is that of “social proof”. We all tend to take the lead from other people; if everybody does something, or says something, most of us join in before we think about what we really should do. Auctions put you in intimate contact with other people who are all providing social proof that the sale item is important and valuable.

“It is not enough to succeed. Others must fail.” — Gore Vidal

the competitive element of auctions is crucial to provoking our irrational buying behaviour. Once we’re involved in an auction we’re not just paying to own the sale item, we’re paying to beat other people who are bidding and prevent them from having it.

Still curious? The best book you can read on the subject of psychological influence is still Robert Cialdini’s Influence.