I agree 100%, reviews should never be a surprise. But it's amazing how people have selection attention. I've told people that they were headed for a below average rating and found them to be surprised when they received that. It's tricky when you have an employee with performance issues, because you want to focus on the parts they're doing right but at the same time you need to give them honest feedback and it can get confusing. "But you said I was doing better."