I have 4 trainees at the moment, they are performing quite well for me, will perform better and better over time, they wont break the bank and in a few seasons i could sell them for huge profits. I have a positive $ balance and stay competitive, even thinking about promoting to div II this or next season. Go figure.
When you'll sell your 4 players, you will need 4 new players to keep the same level in your roster, so in the end you'll win nothing. For exemple, I've bought a pre-trained player 4 millions, I give him additional training, now his value is 8M. Great for my bank account? No, it's a good thing for the strength of my team, not for my bank account. If I sell him and I replace him with a player of lets say 5 Millions, I will earn 3M but my team will lose a lot of strength...
I've started to play this games 3 IRL years ago and it's only now that I have a good team, I don't say my strategy was optimal but I think I was quite fast to build and buy my team. 3 years is already very long and I understand that lot of people lost their motivation before and quit the game.
Now, with the price market rising, I guess it's not 3 years from scratch but 4 years. They have to reduce that factor if they want to keep the newcomers.