I'd say the problem is at L25 is when players get to what by Mafia Wars terms in this game as known as the "Shark Tank" and most managers would have 5* or better players already in their team so they don't need to buy whats on the market and most possibly the young players at 5* (if any) are the most sought after players, everyone by then at L25 will be too experienced to know whats going on in the game.