[type0]

The problem is that you get counter down-votes for those explanations and that quickly turns into flame wars. As is it now everyone free to comment on why they downvote someone. I can see it being useful to not allow making too many downvotes for one person for one day. This way knowing that your downvotes are limited you could spend them wisely.

[ocdtrekkie]

That's why I would keep those downvote explanations private to the people being downvoted. And don't have them part of the vote/downvote system.