To me it is a waste for a kid to leave early not being guaranteed that you will get drafted. Also a lot of horror stories about a lot of the European leagues or other countries where they don't always pay you on time or at all. If you are not playing in the best European leagues then you are really taking a big chance on whether you will get paid or not. Staying 4 years really hurt players like /Duncan, Ewing, Robinson, Bird and a lot of other players I mentioned and when those guys played the NBA was a lot better to watch.