NBA franchises spend anywhere from 50 million to 100 million on yearly salaries, plus another few million per year evaluating and developing players. For a scout or general manager (I've only been the latter), seeing a prospect for one measly four-month season of college ball increases the risk of being wrong about his potential. Remember, talent evaluation is a business in which, in the words of Jerry West, the greatest GM of all time, "Being right 51 percent of the time means you're doing well." Having an extra season to assess the potential of college players would cut down on the personnel mistakes that teams inevitably make in the draft, something that could potentially save the league tens of millions of dollars every year.