Quoted from GotAQuestion:I like the upvote feature, I feel like nobody on any forum uses the downvote correctly. I've always felt downvotes should be used to handle trolling or posts that do not contribute. Instead it's almost always an "I disagree" or an "I simply don't like you" button. And often it's just another kick in the ribs to a post where someone's opinion goes against the hive mind (posts that hit -1 are a lot more likely to go further into the negatives). Nothing can really be done to fix that though.
But the down vote literally means "I disagree".