It's not that I don't believe it to be true, only that we do not require people to force themselves to read subject matter they would rather not, or have been warned against. You may be capable of complete objectivity, but that can't be said of everyone.
Or, alternatively, they can skip the third question, which is specifically for how much one liked a story. We average each question separately, too, so that you can skip (any) one, yet vote on the others.