The sunk cost fallacy

You'll understand that a sunk cost is money or effort already spent that can't be recovered, no matter what decision you make next.

You'll see how people irrationally keep investing in failing projects just because they've already spent so much—and recognize this trap in real life.

You'll learn the counterintuitive logic: only future costs and benefits matter, so past spending should never influence what you do next.

You'll discover why our brains are wired to feel loss so deeply that we chase bad investments—and how recognizing this can help you break free.