Thank you for both of these examples and adding your thoughts. I meant to reply earlier but it slipped my mind.

pain is definitely a lesson delivery system and I think that many only learn how strong they are where the suffering is deep enough.

In Finland there is a term called Sisu, which is similar to grit in some ways. It is the reserve energy that gets accessed when facing deep adversity. I disagree with their definition though for in my view the energy is always there, I believe it is always accessible, we just haven't learned how unless under extreme stress.