Often times it is very difficult for an employee to identify the reasons why they are not performing up to expectations (this even applies to the revenue model).
In our research, we have also found that a culture driven only by numbers and money typically produce unhappy employees and decreased morale. Cultures that are driven on improvement and achievement through performance tend to produce happier employees that are excited to work for a what is likely unique company.
Ultimately, we created MicroEval to increase the conversations happening in the work place. And we want to provide the participants of those conversations concrete things to talk about. Having identified the nuances of one's performance gives them a clearer target for improvement.
I think performance reviews can be eliminated entirely. VPs that are in charge of products could be evaluated on how much revenue their product brings in. VPs could have the power to fire anyone working under them. Same with the managers working under the VPs.
The idea is to motivate employees to achieve one thing: bringing in more revenue (which is the goal of all for-profit companies anyways). There's no need to slice and dice the "performance" into pieces. Just empower people and measure revenue.