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psychology

Sunk cost fallacy

What it means

The error of treating already-spent time, money, or effort as a reason to continue. Rational choice ignores sunk cost: what matters is whether the next dollar (or year) is the best use, not what you’ve already paid. Common in failed projects and relationships.

Related concepts

Loss aversion
System 2 thinking

Cross-reference·Sunk cost fallacy on Wikipedia

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