Research suggests there may be race, sex, and ability differences in score improvement on different selection tests and methods when retested (Schleicher, Van Iddekinge, Morgeson, & Campion, 2010). However, it is uncertain what individual differences moderate retest performance on GMA assessments, and why. In this study, 243 participants were retested on the Wonderlic Personnel Test (WPT). There was no evidence that race, sex, emotional stability, or conscientiousness moderate retest performance on the WPT, although SAT scores did positively predict retest performance. Individuals within the interquartile range of the initial WPT scores gained more when retested than those with more extreme scores. Establishing artificial cut-off levels demonstrated that those below the cut-off gained more when retested than those above the cut-off. Therefore, average-scorers and in some cases lower-scorers who may have failed to meet a predetermined cut-off are encouraged to re-test as they have little to lose and much to gain.