Competition judges are often selected for their expertise, under the belief that a high level of performance expertise should enable accurate judgments of the competitors. Contrary to this assumption, we find evidence that expertise can reduce judgment accuracy. Adaptation level theory proposes that discriminatory capacity decreases with greater distance from one’s adaptation level. Because experts’ learning has produced an adaptation level close to ideal performance standards, they may be less able to discriminate among lower-level competitors. As a result, expertise increases judgment accuracy of high-level competitions but decreases judgment accuracy of low-level competitions. Additionally, we demonstrate that, consistent with an adaptation level theory account of expert judgment, experts systematically give more critical ratings than intermediates or novices. In summary, this work demonstrates a systematic change in human perception that occurs as task learning increases.