Downvote with no explanation

Question

I find it quite irritating and not beneficial at all, when someone downvotes my question without any comment to say why. The current question is this, but I have seen this situation on many other questions. Sometimes you can find at a downvoted question a comment from the asker himself asking "Why the downvote?" or something.

As I understand it you may downvote a question if

• it has a poor quality
• it is not clear
• no web research has taken place beforehand = laziness (obviously hard to prove though)
• no SO research has taken place beforehand = laziness
• it is a duplicate
• it doesn't explain the issue well enough or I can't understand it
• ... etc.

Am I right or wrong here? There doesn't seem to be a topic about voting in the FAQ. I found some questions here on meta that give good clues, like this and this. But they always talk about peoples own opinions. Are there no official guidelines to upvote and downvote? (Well, there MUST be, so why can't I find it?!)

And to the downvoting-without-leaving-a-comment issue:
Any others who can't see the logic here either? What is downvoting good for when I am convinced that my question is fine for the site? Have this been discussed before?

Update

So, I have found that the documentation on how and why to downvote can be found in the list of privileges: https://stackoverflow.com/privileges/vote-down.

Still though the explanation on when to downvote and what to do about it is not very thourough.

Update 2

I have been thinking a lot about the comments on anonymity. I understand the deal here.

So, wouldn't an idea be then to simply require an anonymous comment from a downvoter? If that could be build into the system.

Answer 1

Are there no official guidelines to upvote and down vote?

The privilege page says:

When should I vote down?

Use your downvotes whenever you encounter an egregiously sloppy, no-effort-expended post, or an answer that is clearly and perhaps dangerously incorrect.

Apart that, there isn't anything official about down-votes. Consider what shown in the tooltip for the down-vote button:

This question does not show any research effort; it is unclear or not useful (click again to undo)

For example, suppose that a user ask a question that is duplicating another one; the question is closed, and the OP asks exactly the same question, asking again the same question, when the previous question is closed. I would not be surprised the user gets down-voted.

The reasons why who down-votes doesn't always leave a comment are probably two:

• If a user always leave a comment when down-voting, it would be easier to notice when that user down-votes. Down-votes are anonymous by design.
• There isn't a reason to leave a comment, if the down-vote is given because the question doesn't show any research effort, or it is not useful. What would the comment be, in those cases?

Answer 2

Even if in some case is easy to tell to the other –you forget that- and not downvote, and the user corrects it, in the rest cases for my point of view, to not left a comment may help more the one that make that post.

Why ?

If you not get any reason for the downvote you need to search by your self to find the reason, if you really care of course to improve your self.

So if you search by your self to find the reason of -1 you may find ten reasons and not only one, not only the one that the user gives you -1.

And if the user gives you a reason, this is easy to argue with that and avoid accepting this reason, avoid improving your self and being a better one. Its easy to say, this is your personal opinion and I am not accept it - but this way you never really learn anything, you stop only to what you believe is correct. Like some people that make a question, that have all ready stack on an non working answer and did not open their mine to see some other answer that may work.

So find by your self why you get -1 can real make you better.

The same think happens in life, life is push you on your mistake, gives you -1 and no one is there to give you a reason, and if you not see why you get slaps and continue that road you never be better person.

So search by your self why the -1, find more than one reason, and the next time correct all that reasons.