Money
Sunk cost
Money or time already spent that you can't get back. The sunk cost fallacy is carrying on with something because of what's already gone into it, rather than what it will return.
You'll hear it as
We've spent a year on it. That's a sunk cost, not a reason to keep going.
Why it matters to you.
Projects that should be stopped often survive on sunk cost. Judge them on what they'll cost and return from here.
Related terms.
Videos.
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