The Sunk Cost Exit

The hour you already spent is gone whether you stay or leave. The only thing you still get to decide is what to do with the next hour.

That is the sunk cost idea. Money, time or effort already spent cannot be recovered, so it should not steer the next choice. Yet it does, constantly. We finish bad meals, bad books and bad projects because stopping feels like admitting a loss.

The one-line test

Ask yourself: If I were starting fresh today, knowing what I know now, would I sign up for this? If the answer is no, the past is the only thing keeping you in your seat.

But do not overcorrect

Past effort can still matter in legitimate ways. If you are nine tenths through a project, the remaining cost really is small, so finishing may be the right choice. That is about the cost ahead of you, not the cost behind you. Commitments to other people count too.

Good places to try it

• The subscription you keep because of what you paid to join.
• The repair that keeps costing more than a replacement.
• The hobby you only continue because of the gear you bought.

Leaving the movie is not a failure of nerve. It is simply arithmetic with the right numbers in it.