The golf tour system evolved more by trial and error than by design. In the early days of professional golf in each region of the world each professional tournament was established by a separate golf club, golf organisation or commercial sponsor. As the number of tournaments increased the most talented professional golfers concentrated mainly on playing in tournaments rather than on club professional and golf instruction work. Once a good number of tournaments were being played in a region each year they were formalised into a "tour", which was supervised by a single organisation, although individual tournaments continue to be run by separate bodies in many cases.