Was it physical strength and athleticism? Intellect? Leadership ability? Well-roundedness? None of the above. The best predictor of success, the researchers found, was the prospective cadets’ ratings on a noncognitive, nonphysical trait known as “grit”—defined as “perseverance and passion for long-term goals.”10 The experience of these army officers-in-training confirms the second law of mastery: Mastery is a pain.
