Answer:
They aren't born wanting to fight they are raised and taught to. If your talking about a grown pit then you'd know if it goes around another dog and shows major aggression then you have a lot of work to do. But if it's friendly (doesn't snarl, growls, foam at the mouth, or has it's back hair standing) then your lucky. It takes a lot of work and energy to break a pits fighting habit. But it's do-able.
They are just doing what there owners tell them to do!If you get one you will be so happy THEY ARE THE NICEST DOGS EVER