Decision Mastery Check the Evidence

Sunk Cost Stop

Say this

Would I start this today if I hadn't already started it?

Do this now 2 min

Write down what you've already invested — time, money, reputation, effort. Now cover it with your hand and ask: "If I were starting fresh today with none of that invested, would I choose this path?"

Use when

You're continuing something primarily because of what you've already put into it.

Avoid when

The investment genuinely increases future value — not all persistence is sunk cost fallacy.


Why it works

Past investment is gone regardless of what you do next — but the brain treats it as a reason to continue, trapping you in losing positions.

The money is spent. The time is gone. Nothing you do next changes that. But your brain doesn’t process it that way — abandoning a failing path feels like confirming a loss, which triggers the same pain circuits as physical injury. So you keep going, hoping to ‘recover’ what’s already unrecoverable. The physical act of covering your past investment — hiding the number — separates what happened from what happens next. The only question that matters is: knowing what I know now, would I start this today? If no, the answer is already clear.


Go deeper · 8 min read
The Sunk Cost Trap: Why You Keep Investing in Losing Positions
Everyone can recite the sunk cost rule and still escalate. The reset question fails for senior people because the cost being protected was never really financial. It is your standing for having chosen the path.
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