Can it ever be justified in down voting a technically correct answer, or an answer with a minor error that can be corrected when brought to the attention of the person who answered the question. I reluctantly deleted an answer that was correct because it annoyed me seeing the down votes and felt quite angry when I was awarded a "peer pressure" badge.
There are many possible reasons for down-voting that have nothing to do with correctness in a narrow sense, including:
- DVer thinks the answer is too sloppy.
- DVer thinks the answer is too terse.
- DVer thinks the answer is redundant.
- DVer thinks the answer is too clumsy.
- DVer thinks the answer uses needlessly advanced tools.
Or, DVer thinks the question just should not be answered.
Thus, in short, yes it can be justified. Whether in some given case it is the best course of action is hard to tell in abstract, and opinions on that matter are quite mixed.
You can downvote a person for using the number 3, because you hate 3
There are no rules on downvoting so long as one doesn't arbitrarily abuse the system. Then the mods might step in and remove rep powers, scold the user, etc. But it would take a lot for that to happen. I can go click a random question, downvote an answer, and it is completely within my rights. Why do you think there is a daily limit? Also, it /costs/ the user to downvote by one vote. So, not only is the user limited in their ability to make unjustified downvotes, but they also have to be willing to accept the same downvote. As a result, it's a fair system.
Plus, most answers aren't downvoted for no good reason. Now, I know that's cliche, but it's the norm to upvote a decent question/answer. So in the end, you're going to either be pushed off the site and answer/question BANNED due to "low quality posts" or you're going to make a decent trend towards gaining large quantities of reputation.
I think the theme of this question is a matter of site policy, not opinion. So, I'd like to make one final point. Moderators cannot feasibly monitor every piece of reputation. If they did, the site would be filled with messages involving people having to "justify" an up/down vote. The manpower necessary would be insane, asinine, and result in bogging down the site. Like I said at the beginning, only flat out blatant abuse is going to be seen and moderated.
(Too long for a comment):
@quid "DVer thinks the answer is too sloppy, DVer thinks the answer is too terse, DVer thinks the answer is redundant." These are subjective reasons. What I'd like is objective reasons.
""DVer thinks the answer uses needlessly advanced tools." Yet if you surf this site, others have suggested that (something along the lines) "advanced answers provide food for thought for the person who asked the question and for others".
As far as homework question's go, I've noticed that these questions have in many cases been edited to make the question more sensible. Shouldn't they have been rejected at this stage? Shouldn't homework questions be automatically reviewed and rejected (if necessary) before hand? As well, I've been criticised about answering questions where someone else has thought there wasn't enough effort. When I pointed out why I thought some effort had been made, these haven't been answered.