Given that the detailed original criteria for deliberate practice have not changed, could the understanding of this complex concept have improved over time? A response to Macnamara and Hambrick (2020).

In their commentary, Macnamara and Hambrick (Psychol Res, 2017) accused my colleagues and me of systematically changing the definition of the concept of deliberate practice. Deliberate practice was the result of a search for characteristics of effective practice in the laboratory that was shown to improve expert professional performance in domains, such as music. In this reply, I will first describe five different criteria that defined the original concept of deliberate practice and each of them is presented with directly supporting quotes from Ericsson, Krampe, and Tesch-Römer (Psychol Rev 100:396-406, 10.1037/0033-295X.87.3.215, 1993) paper. Unfortunately, Macnamara, Hambrick, and Oswald (Psychol Sci 25:1608-1618, 10.1177/0956797614535810, 2014) misinterpreted our concept of deliberate practice, and defined it much more broadly: "as engagement in structured activities created specifically to improve performance in a domain" (p. 914). This definition led them to include activities, such as attending lectures, studying alone by students, and group activities led by a coach, where each activity does not meet one or more of our criteria for deliberate practice. In this commentary, I will argue that Macnamara and Hambrick (2020) became aware of some of the original criteria for deliberate practice, such as the role of individualized training by a teacher, and these discoveries misled them to assume that we had changed our definition. The intended meaning of sentences that Macnamara and Hambrick (2020) had carefully selected is shown to have an appropriate interpretation in Standard English that is consistent with our original definition of deliberate practice. In conclusion, I will give a proposal for how the different perspectives can be reconciled.