Quality of practice is also important, and probably a major factor in your example. My knowledge and skill will be vastly different if I spend 500 hours playin

Quality of practice is also important, and probably a major factor in your example. My knowledge and skill will be vastly different if I spend 500 hours playing against the best players in the world, compared to spending 500 hours playing in Bronze league (does Dota2 have a bronze league?).