Possible Duplicate:
Is it now discouraged to ask for reasons for downvotes as a comment?
A few hours ago, an answer of mine was downvoted, with no explanation. I left a comment that was along the lines of: would someone care to explain the downvote? Now I notice that my comment has been deleted (I suppose either automatically from flagging or by a moderator).
I thought my comment was reasonable—I don't think that my answer is wrong or unhelpful and would appreciate knowing what might be wrong with it. I don't particularly expect the downvoter to provide an explanation (he or she could have done so when voting), but someone else may see the same flaw(s) and provide some enlightenment. (This has, in fact, happened to me before and the explanation led me to improve my answer.)
Why was the comment deleted? Are such comments now considered unconstructive or something?