In this article, the last in a series of four on performance appraisals and how they relate to safety, I want to discuss six psychological factors that prejudice typical performance evaluations. Remember, generic evaluations and rankings won't improve competence - in safety or any other area. Still, becoming aware of these factors can make your evaluations more accurate.

But if everyone gets a similar above-average score on a generic performance evaluation, the rating process has limited value. This is a prime reason for eliminating the traditional evaluation and ranking component of a performance appraisal system.