You must not be familiar with several studies done on the lives of retired athletes, not only in the NBA, but in ALL major sports. Many athletes, after they leave the game, have no marketable skill set. Add to that the fact that many of them spent and invested poorly, and so they file for Chapter 11 or are relegated to the bargain-basement life of signing autographs at card shows. And this is for great to hall of fame players. A fringe player has less opportunity to succeed after he leaves the game. Not all players get european contracts, front office, endorsement or broadcasting jobs, and most are left to float aimlessly.
Point being, an athletic career may not need a degree, but those careers are often short lived, due to either age, injury, or erosion of skills. In those cases, a college degree, even a partial one, can help a player either to resume his studies, or to find some degree of higher level work in this society.
The immediate effects/advantages of jumping straight to the NBA from high school are undeniable, from a purely financial perspective. However, placing an individual in college environment help them not only to mature and learn some life skills, but skills they can use for further employment, in case they blow out a knee, get cut after their first contract, etc. I support the logic that is willing to sacrifice the Kevin Garnetts, the Kobes, the LeBrons, and the McGradys for a couple of years to save the others from themselves, and their inflated opinion of their own ability. Since most players are too foolhardy to realize their basketball skills might not be there forever(or may never reach NBA levels) an age limit that nudges them toward college(but does not FORCE them) "insures" them for later life.
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