What's a phrase that describes a person who keeps making repeated attempts that they know are doomed to fail because they don't want all of their previous effort to have been for nothing?
They feel like they can't give up at this point because they've already put so much of their time/money/effort/etc into accomplishing it.
At this point they probably regret having even tried in the first place, but now that they've dug themselves such a deep hole they feel pressured to just keep digging —
— almost as if the hole they've dug is already too deep to climb out of, but they've convinced themselves that if they just keep digging eventually they'll reach the other side and pop out in China or something.
A gambler who has bet and lost thousands but continues to throw more money away so that the money they have previously bet would not have been for nothing.
Someone who keeps on buying lottery tickets so their previous purchases won't have been a waste if they could just win one time.
Someone who tries to build something over and over and over again, and every time it fails — and at this point they've realized that it's probably never going to work but they feel like they can't give up because then all of the time and effort that they have already put into it would have all been for nothing.
To be clear: This person does not want or need to commit to this course of action — in fact, it'd be much better for them if they were to stop before they make their situation any worse — but they feel pressured to keep going anyway, desperately hoping that it will eventually pay off even though they know at this point that it undoubtedly won't.
Thank you so much for your help!