This is review suspension. It could happen to reviewer who frequently observes the message looking like:

![http://i.stack.imgur.com/fKYEP.png][1]

Above message indicates that user failed a [review audit](https://meta.stackoverflow.com/tags/review-audits/info):

> ###Test items in review queues that are designed to help new reviewers hone their moderation skills, while nudging more experienced users that don't seem to be paying close attention to what they're reviewing...

  [1]: http://i.stack.imgur.com/fKYEP.png