This only works if the feedback loop is closed - as in you see a trend line, correlation, something (anything) that allows you to see value in your perseverance.

If you get no feedback after years on end... watch out

There are too many religions that glorify martyrdom where destruction of self can be seen as a honorable end. This when coupled with these grit narratives, make for very scary things.

The internal dialog must be carefully tuned to a feedback system. And not just any feedback system, one of the individuals chasing (a is intentional). Without proper nurturing, one begins to lose the self - leading to many terrible things.