The Psychology of Sunk Cost
Hal Arkes & Catherine Blumer · 1985
"People irrationally continue investing time, money, or effort into a failing course of action specifically because of what they've already invested — even though that past investment is gone regardless of what they do next, and only future costs and benefits should matter to the decision."
In one of the paper's field studies, theatergoers who paid full price for a season subscription attended significantly more plays over the following months than those who bought the same subscription at a discount — the higher sunk cost created a stronger pull to keep attending, even though the ticket price had no bearing on how enjoyable any individual play would be.
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Motivated Stopping
"When you want to believe something, you stop looking for evidence at the first confirming fact. When you don't want to believe it, you demand impossible proof."