I don't think I was very clear. My main concern is that people will move something down because they disagree. There can be a comment I disagree with very much

I don't think I was very clear. My main concern is that people will move something down because they disagree. There can be a comment I disagree with very much but if it's well reasoned and on topic I can't really punish the author only on the basis of me not sharing the same opinion. And that's what I feel is happening quite often. It's okay in the cases of foolish and unreasonably rude comments, there's no question about it. But in cases where you simply disagree its uncalled for. In the case of uninteresting comments that don't qualify as rude or foolish I don't think there's a reason to downvote. Instead you up vote the good ones around it and let it just stagnate. Downvoting is a way you can kind of give others hints of the kind of things that are expected around here. If you downvote on the basis of it not being interesting the person may come to believe they've said something offensive or foolish when really it was just boring. If they see they're getting no up votes then they can kind of tell that what they said was boring without giving them the wrong impression. People who get severely downvoted definitely get the hint if they're being off topic or foolish but when they're downvoted for being boring I don't think they get it and may think something else is up.