I would like to propose a possible solution to serial anonymous downvoting. Sometimes the phenomenon occurs within a short space of time, and in that case the system detects the voting irregularity and within 24 hours reverses the downvotes. This system works and is an effective deterrent to would-be revenge-downvoters, as it means they are also identifiable to the moderators.

But what happens if the series of downvotes is spread over a distance of time? With not one downvote explained, justified or used as an aid to help the user improve his or her question. What then?

That's an impressive list, isn't it? :) I'm not insinuating that I didn't deserve any of the downvotes. I'm not suggesting that the person responsible did not have any good reason for not downvoting. What I am saying is that this person, (who no longer has an account in ELU or in ELL) systematically and deliberately downvoted my questions and answers anonymously. And because his account has been deleted I know exactly who the user was, which makes the downvotes that more unpleasant and sadder. And I swear if he had once or twice indicated why my answers or questions were weak, I would have listened to his criticisms and have adjusted my answers accordingly. But he never did.

Once, confidentially, when I was unaware of his duplicitous behaviour, I even asked him why I might be receiving so many downvotes. He said I sounded too arrogant and lacked humility. Well, that was a shock. But I listened and thought maybe I do sound like that. Maybe the voice which I hear in my head while I'm writing is different from the one others hear. Nobody wants to be disliked, even if it's on the Internet; it's a fact. Consequently, I attempted to soften my comments especially on Meta, and tried to be more diplomatic. Funnily enough, things improved a bit, and I thought my "advisor" had given me some sound advice. Ha! (That's an ironic "ha!" by the way)

I have to say in his defence, he also upvoted a few of my answers and questions, but he would nearly always leave a comment. Now these few sparse comments have been deleted along with his account, which explains how I know who the person was.

Anyway, here is my idea on how to discourage anonymous downvoting. It is something which I suggested some time ago on Meta Stack Overflow but it didn't make a chink in that sea of comments, arguments, discussions which have engulfed that thread. See the link below.

In brief:

• for every five downvotes a user leaves without a comment he should lose 5 rep points.
• On the fith consequetive downvote a visual reminder should appear advising him/her to leave a comment.
• If the user explains one downvote in five, no change in rep points occurs.
• The downvoter needn't specify he or she is a downvoter, as long as the comment is constructive and legible.
• Any user leaving meaningless incoherent comments or insults ought to be flagged by the community, and have 5 points deducted if he/she refuses to edit their comment.

I don't think it is an infallible solution, and for high rep users losing five points is peanuts but... at least they will be some form of penalization for anonymous (at times inexplicable) down-voting.

Encouraging people to explain downvotes

I would have written an "answer" but I haven't nor ever will, earn 10 rep points, on this site so, I have to make do with a long comment. I read one suggestion made by mg1075 who might be onto something. What if instead of [earning] a badge, as he suggested, for every five downvotes with no comment you lose five rep points? Cont'd. – Mari-Lou A Sep 17 at 7:32

Cont'd ... This will still allow leeway for: 1. You just want a quiet life and no hassle. 2. to explain why would take too long. 3. Your downvote is confirming the general consensus that an answer is incorrect. 4. You're in a mean mood. But on the 5th consecutive downvote you would need to make a constructive legible criticism. Anyone who writes a mangled comment would be immediately spotted and be flagged by the community. I'm not sure if this idea has already been suggested, so apologies if it has been and was rejected.