The final problem with the ten-thousand-hour rule is that, although Gladwell himself didn’t say this, many people have interpreted it as a promise that almost anyone can become an expert in a given field by putting in ten thousand hours of practice. But nothing in the study of the Berlin violinists implied this. To show a result like this, it would have been necessary to put a collection of randomly chosen people through ten thousand hours of deliberate practice on the violin and then see how they turned out. All that the Berlin study had shown was that among the students who had become good enough to be admitted to the Berlin music academy, the best students had put in, on average, significantly more hours of solitary practice than the better students, and the better and best students had put in more solitary practice than the music-education students.