This is not a question. You need to define "terrible."
Example:
Q: Why do you want to be a doctor?
A: So I can be filthy rich and get laid every night.
Versus
Q: Why do you want to be a doctor?
A: I guess it's something I've always wanted to do. Not sure why. I've just always been scientifically minded.
Both terrible answers, but the first candidate will not get accepted by that school (I can almost guarantee that) whereas the second candidate may get a slide if everything else, including rest of interview, is good.