Maybe I'm cynical, but in my experience, performance reviews have very little to do with managing employee performance. They are a bureacratic ritual that lets the company demonstrate they have been managing your performance.
This is useful to the company if they want to let people go, to mitigate any legal risks. They have a record that your performance was being managed. Even though 9 times out of 10 there was no actual management throughout the year.
I got dinged on my performance review for being away from my desk. Didn't stay long at that company.