Is not with time, is due recuction of stars when seasons are passing and, adding new players, this can change the performance of other players + the % of effectiveness, for example I had Nedved as my best man for fouls, since I added layers and suddenly started failing in massive mode lol
Too I remember 2 sub's that i had (or maybe I keep one?) and when they came to the field as subs' the team start failing and with 1 when he appeared = 1 injurie in 90% times lol
This was sold.