Pretty much self-explaining. What are the reasons behind not being able to see who upvoted or downvoted posts?
Voting is anonymous by design (see also this thread), although I'm having some difficulty tracking down an official word or SO meta discussion as to why. I'm fairly certain it has to do with two related things though:
- To keep the focus on the site on the questions (and answers) and their quality.
- To prevent retaliatory voting and/or comment drama.
If a user wants to reveal their vote, they can do so in a comment, and it's generally considered polite / good practice to comment on a downvote especially if you are the first person to do so.
This is an unofficial best guess:
Negative votes are not meant to be taken personally but its very easy to do so even without knowing who did it. I think knowing who is down voting something could cause some unneeded drama such as
"@UserWhoDownvotedMe - WHAT IS WRONG WITH YOU? My post is PERFECT!!! Give me 27 good reasons that my post deserves a down vote!!!!"
And all of a sudden its personal all around when really the whole point of downvoting and closing questions is to keep the site on the right track. I think by exposing who is doing what voting there is going to be a lot of negative feelings towards certain users who consistently downvote things for the greater good of the site. These users will undoubtedly receive a lot of negativity from users and then probably just get fed up and leave the site which has a very negative impact on our community.