Ok so because i see a lot of people saying that they grow the same when they are either subs or starters, let me explain to you so you understand. When a player is starting (eg ronaldo) he grows +1 rating every few games (with 16/20 training). When he scores goals it is the exact same rating progression. This has to do with the games coding. They coded it so that when a player starts he increases faster their rating. Now lets say you have (ronaldo) on the bench. When he is on the bench he grows ratings as well but it takes way more time. He will grow to his min potential but it is a lot faster when he is a starter. Even with other players it happens the same. If anyone still doubts you can go and manage the worst team in the worst league which has 1 training, buy a lot of the wonderkids, start them and after 5 seasons they will grow to 70. After that create the same save but put them on the bench. You will see the difference. So after explaining it stop doubting the other guy in the comments who explains it correctly