"Studies of people with extraordinary abilities, like Ted Williams, have given rise to what Swedish psychologist Dr. K Anders Ericsson called the "10,000 hour" rule. The rule's premise is that, regardless of whether one has an innate aptitude for an activity or not, mastery of it takes around ten thousand hours of focused, intentional practice. Analyzing the lives of geniuses in a wide range of intellectual, artistic, and athletic pursuits confirms this concept. From Mozart to Bobby Fischer to Bill Gates to the Beatles, their diverse journeys from nothing toward excellence in their respective fields shared a common denominator: the accumulation of ten thousand hours of unwavering "exercise" of their crafts."