(Inspired by the Kuja topic.)

Why are the bad guys in Final Fantasy "bad" to begin with?

Sephiroth thought he was an Ancient but now just wants to be like his "mother".

Ultimecia feared the SeeD who woul dkill her.

Kuja wanted to prove his existence and to avoid death.

And I think FF1 Garland was afraid of some prophecy foretelling his death and that's why he did the loop thing.