Deliberate Practice is best conducted alone for several reasons. It takes intense concentration, and other people can be distracting. It requires deep motivation, often self-generated. But most important, it involves working on the task that’s most challenging to you personally. Only when you’re alone, Ericsson told me, can you “go directly to the part that’s challenging to you. If you want to improve what you’re doing, you have to be the one who generates the move.