When to quit an early stage startup

About me: 25M working in a super early stage startup for 1yr.

The startup is only 2 yrs old with seed funding. 2 pivots, but none worked. The 3rd pivot is interesting and we still don't know if it'll work

I want to understand the life of an Early employee, how do you manage to keep hope, or when to call it quits?

Have vested esops. Also feel if I can get 1.5X cash salary if i switch