What I mean is how fast and slow the player trains. The higher the training level, the faster that player pops, but salary has to be taken into account. Like I said, if you plan to stick with this guy long term, and you have the money, then more power to you. But if you will think of selling him before he is finished training, then you only need an advanced trainer. Of course, a trainee won't pop every single week, especially as they get older. But there are things called sublevels, that look like this for example: .33, .46, 9.23, etc.