Exceptional performance doesn’t happen without exceptional effort, and even allegedly inherited abilities — like IQ and other “smartness” measures — improve markedly and continuously when people work hard, have good coaching, and believe they will keep getting better. The nature versus nurture debate persists in academia and society. But natural gifts are useless without lots of practice. People, teams, and organizations that are novices at something almost always do it badly at first; brilliant or at least competent performance is achieved through raw persistence, coupled with the belief that improvement will happen. What people are able to do as beginners is far less important than whether they try hard and keep learning every day.
Research in dozens of domains reveals a similar story — exceptional performance doesn’t happen without approximately 10 years of nearly daily, deliberate practice, for about four hours a day, by people who somehow (e.g. coaching, skilled peers or competitors, or books) have access to the best techniques. This 10-year rule holds in every domain — chess, medicine, auditing, programming, bridge, physics, juggling, dance, and music. And once achieved, exceptional performance can’t be maintained without relentless effort.
— Hard Facts by Jeffrey Pfeffer and Robert I. Sutton