Hello
This is one of things that BB is a crazy and fun game.
To soluting this problem, I ever say: "I look to Offs". You training hard your player in regular season and on Offs, train Free Throw and put the players in your best positions.
At same time big mans need to train OD, defensives outside players need to train SB.
If you don't wanna loss games or training out position, buy a complete player and win games.
Your goal is same: win.
The way is the choice:
1 loss regular-training; or
2 win regular-buying.
On first, you have income and still the cash but need some seasons [Pros Revenue; Against Time]
On second, you pay with cash but gain time [Pros Time; Against Revenue]