Greta is everyone's favorite coworker. She is enthusiastic and helpful. Her work is subpar. Manager Hector awards Greta with positive performance marks, even though she did not earn them. This situation exemplifies which of these reasons why performance appraisals can fail? overemphasis on uncharacteristic performance manager rating employee's personality rather than performance inadequate preparation on the part of the manager inconsistent ratings among supervisors or other raters