decisions
Sunk cost fallacy
The money already spent is not a reason to spend the evening too.
You have already spent $60 on a project. It will cost another $40 to finish. A new option appears that gives the same result for $30 total. What do you do?
$60 already spent
Finish the original project: $40 more
New option, $30 total
Same result
The $60 is already gone either way.
Only the future cost matters.
Choosing to finish only because of the money already spent is the sunk cost fallacy.