Pleyers progress

can someone explane me what affects the progress of players... someone told me that young and expensive players progress faster but then i bought 2 18 years old players ( 2.5 mil and 3.2 mil , it is pretty much cause i am lvl 3) but they earn around +60 skill progress after the league match so i think it is pretty low... i have few older players who wroth around 1.5 mil each and they progress much faster ( around +100 after the league match) can i get answers please ?

It depends of their performance in the game. If they strike 3 goals, they will reach 150 (it's an example) easily, if they have done almost nothing, they will have low a progress result. And I don't know if we can add the training intensity to it, but if yes, be sure to set it up at max performance.