This effect is also well known by people who play in minor or collegiate level sports, who then move up into professional or major leagues. The distribution of

This effect is also well known by people who play in minor or collegiate level sports, who then move up into professional or major leagues. The distribution of good players becomes way more concentrated, for each team is now composed of all of the best players from the lower leagues, and many rookies suddenly have to achieve new levels of excellence. Many don't. Talk to most semi-pro or collegiate athletes and many of them will readily admit that they have no chance of making the professional leagues, even if they are better than everyone else on their team. The skill differential between the leagues isn't linear, it's exponential. Pro players are not just better than amateur players, they're 10x better.