How often do you receive complaints about the annual performance review process?

How often do you receive complaints about the annual
performance
review process?
What concerns do supervisors have?
What ideas do employees have for making the review
process
fairer?
Do you ever hear supervisors or employees talk about how to
make
the process more goaloriented?
Other than the frequency of reviews, what are some other
explanations
for why employees make these complaints?