Sunk cost fallacy
From ACT Wiki
Cognitive bias.
The sunk cost fallacy is the tendency of individuals and organisations to be more likely to continue with a project if they have already invested a lot of money, time, or effort in it, even when continuing is not the best thing to do.
This is sometimes known as "throwing good money after bad".
One antidote to this tendency is to appreciate that "sunk costs don't count" in rational decision-making.