My understanding is that downvote privileges are limited. I remember reading something a while back that effectively said that if you downvote significantly more than you upvote then you temporarily lose the ability to downvote until your upvote count creeps back up.
This is entirely anecdotal, I have no proof for my theory only a vague recollection of an explanation offered for a similar question at least a year ago.
This is entirely anecdotal, I have no proof for my theory only a vague recollection of an explanation offered for a similar question at least a year ago.