Is doing a big chop always needed?

Doing a big chop is a personal decision, people often are afraid to do so, but it's very liberating to not deal with two structures of hair, but you would have to get to know your hair again.

So NO you don't have to do a big chop, you can manipulate the hair until you are ready to eventually cut it. The "burned" or "permed" or "over bleached" hair will never be the same as your natural hair.