Should managers and non-managers be appraised from multiple perspectives for example by those above by those below and by coequals by customer?

"360 Degree Performance Appraisal"

In Human Resource Management, 360-degree feedback, also known as "multi-rater feedback," "multisource feedback," or "multisource assessment," is feedback that comes from all around an employee that is the feedback is received by those above (Supervisors), by those below (Subordinates), by coequals (peers) and by customers (internal/external customers or suppliers).

It also includes a self-assessment in some cases. It may be contrasted with a "traditional performance appraisal," where the employees are most often reviewed only by their managers or supervisors.

It has been suggested that multi-rater assessments often generate conflicting opinions, and that there may be no way to determine whose feedback is accurate (Vinson, 1996). Studies have also indicated that self-ratings are generally significantly higher than the ratings of others (Lublin, 1994; Yammarino & Atwater, 1993; Nowack, 1992).