“Mastery requires endurance. Mastery, a word we don’t use often, is not the equivalent of what we might consider its cognate—perfectionism—an inhuman aim motivated by a concern with how others view us. Mastery is also not the same as success—an event-based victory based on a peak point, a punctuated moment in time. Mastery is not merely a commitment to a goal, but to a curved-line, constant pursuit.”