The North American sports development system delays athletes' entry into the top level of professional sports until the best of them are ready to make a major impact in their first season.
The typical development path varies by sport: However, in other parts of the world, it is usual for clubs to train their own players and introduce them into the first team gradually.
Occasionally, young players who show extraordinary talent are introduced to the first team during their teens, with notable examples being Wayne Rooney in association football and Ricky Rubio in basketball.
To reflect this difference Young player of the year awards with an upper age limit usually somewhere in the early 20s, are more common elsewhere, e.g. soccer's FIFPro World Young Player of the Year.
However golf's PGA European Tour has the Sir Henry Cotton Rookie of the Year award, and Grand Prix motorcycle racing also awards the top rookie of each class.