I tend to forget to vote to be honest, I should work on that. But when I do vote it's about whether I like it or dislike it, a legit attempt to help, or some putts trolling or throwin some crap answer out.
I vote what I think it deserves but also a bit the opposite of what you said. I don't always bother to vote, and if I see a post that I like has a lot of dislikes I will give it a like or the other way if it has lots of likes and I dislike it I will dislike it. If I like a post and it has a lot of likes already I probably won't give it thumbs up cause it has plenty already