This is one of the things I hate most on SE, people who think downvoting is mean and we should not do it voting to cancel out downvotes, it wastes my vote, your vote, gives to OP rep for a bad post.
Just like silly downvotes exist, silly upvotes exist. The first one probably more often than the latter. I never ever heard of someone, voting to eliminate a downvote however. I doubt it happens, and even if it does, it won't be more then occasionally.
I am having a bit of difficulty therefore with your assumption that the vote was done out of pity and to eliminatecompensate "being mean". What makes you think this vote was motivated like that, and not a random vote, like we see a lot, both up and down?
Although I agree with:
don't vote because you feel sorry for people, you should vote on the quality of the post and not the person.
...I doubt if your anger has a substantially existing target.
Even if it exists, the damage is limited:
it wastes my vote, your vote, gives to OP rep for a bad post.
- Although incorrect, a single misplaced upvote will not eliminate multiple downvotes.
- The rep is the least of our problems. If someone repeatedly posts bad posts, a single upvote won't make him or her an established user. If it was "an accident", the single upvote is meaningless as well.