This [answer](http://meta.superuser.com/a/5612/155990) to another question of mine is the context for this question.  

I have more than once, had the `Post Your Answer` button just move my answer to a question comment for me. But only if it meets or fails to cross some unspecified threshold.  

I propose that the `Your Answer` form submission process _never_ auto-convert a sloppy answer to a question comment. IMO, this will help curtail (instead of actively encouraging) sloppy answers.