Right now he knows exactly what NBA programs are doing and he can do his best to make an environment like that in college.
In 5 to 10 years, the NBA will have drifted towards some different concepts / approaches that he will need to stay on top of if he wants to keep the program relevant with his NBA vision.
Not saying he can't do it - but it does get tough to stay on top of that kind of stuff when you aren't involved with it every day anymore.