From an employer’s perspective, what are the disadvantages of using a pay-for-performance plan?

I have an eight page paper (abstract, title page, and reference do not count as the eight) that is due on 17 March 2018 before midnight. The paper is about “Pay-for-Performance”.  The following questions are required in order to conduct a research. I will send the entire instructions attachment to whom ever accepts my bid.

Questions to Research:
1. How could an organization measure the effectiveness of their pay-for-performance plans?
2. From an employee’s perspective, what are the disadvantages of using a pay-for-performance plan?

3. From an employer’s perspective, what are the disadvantages of using a pay-for-performance plan?