Final answer:
Rater biases in performance appraisals can impact the accuracy of performance assessments and hinder the effectiveness of self-assessment.
Step-by-step explanation:
Rater biases in performance appraisals can account for variability in employee performance. Biases can affect the ratings given by supervisors, peers, and even the employees themselves. For example, supervisors may underrate employees who give themselves modest feedback ratings. These biases can impact the accuracy of performance assessments and hinder the effectiveness of self-assessment.