Have you ever gone through this phase of rewriting your protagonist's story over and over in the fear of not being good? I know I have done it several times in the past and I feel like the reason I always rewrite my MC's backstory is that I didn't give him enough drive about why he left his home to go out on his adventure and I didn't flesh out why he decided to stay in the new place he went to for his adventure and decided to call it his new home. Which led to not enough space for future development on his character. But now I feel like I have the story set out and changed his backstory again, this time in search of his past and what happened to his family. It is cliched but I feel like its better than having no drive at all. So what about you guys? Tell me how many times you changed your MC's backstory in order to flesh them out more.
I haven't rewritten my backstory for my character (his name is Aira Fanel) and also I think doing that would drive you crazy.
I do go through a phase where I write the protagonist's story over and over again, not out of fear, but because my original plan just doesn't work. I've written myself into a wall where the next logical step to resolve the conflict is out of character for the protagonist in that phase of the journey.
Once you see where your crisis point is, I think it's normal to take another look at your MC. You want the decision they make to mean something to them (that's the question you should be asking as a writer), and so you either adjust the crisis or you adjust the MC. You want them to have a moral dilemma with maximum impact. Something that the audience will feel.