Difference Between Mediocre, Great, and World-Class Talent

The difference between mediocre and great talent performance is due to the number of practice hours. That observation is not surprising. What is surprising is the reason for the difference between great performance and knock-down world-class performance, according to Geoff Colvin in his book “Talent is Overrated”. The difference is due entirely  to participating in more systematic and planned-out type of practice hours. Doubling from 2 to 4 hours of daily practice will make you great, but doubling from 4 to 8 hours will not make you a world-class performer.