Recent discussions of strategy development have included the introduction of the concept of utilization deficiency. The present analysis examines the definition of utilization deficiency vis-à-vis the older contrasts between mediation and production deficiency and assesses the logical clarity of the current definition. Further, because utilization deficiency focuses on the transition from initial to proficient strategy use, the present analysis considers all of the possible types of strategy inefficiencies and evaluates whether the current definition of utilization deficiency precludes consideration of important strategy inefficiencies that have been documented in the existing literature and are likely to form the bulk of yet-to-be discovered inefficiencies. Although the emphasis on strategy inefficiencies is welcomed, the current analysis concludes that there are serious problems with the current definition of utilization deficiency, problems that both obscure important theoretical distinctions of the past and limit the investigation of strategy inefficiencies that are likely to play an important role in our understanding of the development of strategy use. Furthermore, the linear developmental model that frames utilization deficiencies from no benefit to sophisticated strategy use ignores the heterogeneity in strategy development that has been recently documented.