Two studies were conducted to examine the implications of inaccurate self-appraisals in online training. Self-assessment of knowledge moderated the effects of trainees' performance on subsequent performance and attrition. Performance was highest after uniformly positive ratings (i.e., high self-assessment and high performance), followed by underestimation, overestimation, and uniformly negative ratings, respectively. Attrition was lowest after uniformly positive ratings, followed by underestimation, uniformly negative ratings, and overestimation, respectively. Effort had a more positive effect on performance following low than high self-assessments and this interaction fully mediated the self-assessment/performance interaction on subsequent performance. Commitment had a more negative effect on subsequent attrition following low than high self-assessments and this interaction fully mediated the self-assessment/performance interaction on subsequent attrition. Finally, trainee conscientiousness affected their behavior when their performance and self-assessments were inconsistent--overestimating and underestimating performance increased attrition more for trainees low in conscientiousness and impaired performance more for trainees high in conscientiousness. (Contains 4 tables and 9 figures.)