"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, a constant pursuit of improvement."