If my comment “adds something useful to [a] post”, I’d simply like to know so - I’d like to be notified. I think that such a feature would, in the long run, improve the quality of comments. Thoughts?
Votes on comments are more similar to favs on Twitter/likes on FB in a way. The only functionality behind comment votes actually is that in case there are a lot of comments on a post, the ones with higher upvotes get displayed by default, not the chronologically oldest.
Question is slightly different than What happens with deleted comments, but the answers given there apply to comment "votes" as well. Comments aren't guarateed to persist, so voting on them doesn't impact your reputations etc.
tbh, I'd like a downvote option on comments too; for the truly idiotic, yet not actually offensive ones - to quickly push them out of contention.
Theoretical wild example:-
OP wants to expand a drive partition.
First comment is 'Wipe your drive, reinstall your OS'
It's not offensive; it's not 'strictly wrong', you could do it that way if you were so inclined; but it would be a whole lot more work than a smarter answer.
As an answer it would quickly get down voted, & commented on itself, hopefully before the OP had chance to take up the idea.
As a comment, there's no 'defence mechanism' for it.