Possible Duplicate:
Down voting consequences
Sometimes down-voting is done without leaving proper comments or reason. The person next-in-line commenting on the post telling them what's wrong might be misjudged for down-voting. This tends to be unpleasant for both the parties. Apart from that, it's always nice to know what a person is doing wrong to get down-voted so that they don't repeat it again, making AskUbuntu a little easier on the editors.
This is a feature request which I am pretty confident will benefit a lot of people and just make AU better on the whole. So, is it possible to have the user fill out a comment or a form just like what pops up when a post is flagged (which can later be attached as a comment to the post) when a user down-votes a post?