I review stories if I find them interesting or not. I base my desire to read the story based upon story codes. if the story has the codes I like, but sucks, I will let the author know that it could be improved. Although, I do tend to rate higher than I probably should, because I don't want to be a complete jerk about things.

You might not have been around for the fiasco with Brenda and her "cheesy feet" stories. Had she put the "feet" code on her stories, I naver would have read them as feet do nothing for me. However, she didn't, so I read one of them and rated it poorly, because it wasn't written terribly well and the content was not interesting to me. I did give it a 4, which, in my opinion, wasn't too bad.

I guess the point to be made is to review the story based on how it is written and how it interests you. if you think the author could have done better, made it more interesting or should use a spellchecker, then tell them. Heck, that's how people improve; by knowing what they need to do to make their works better.