Adopted from the following great insight shared by Charles Duhigg from the book The Power of Habit..

“Highly self-disciplined adolescents outperformed their more impulsive peers on every academic-performance variable,” the researchers wrote. “Self-discipline predicted academic performance more robustly than did IQ. Self-discipline also predicted which students would improve their grades over the course of the school year, whereas IQ did not.… Self-discipline has a bigger effect on academic performance than does intellectual talent.”