I 'm not sure if I can explain it through the program but most from my experience.
some examples -
As I wrote some times, usually my team is based in a group of young fast trainers, starting the season as (high) 5* (end) and ending the season as (high) 6*.
I keep this for some seasons till they get older so I refresh the roster.
Many times happened to me, to play vs a strong team with many players from scout list (you can recognize those players). and won rather easily.
I also observed teams like that, loosing from other lower q teams (in different competitions).
So, you just can't buy today 11 scout list players (or simple players from the market) and expect from them to perform good immediately.
Also if you have 5-6 defenders with double positions (DR-DC, DL-DC), it's good to find in what line you must set them .
Also I observed some super players I had and sold, they did really bad in their new teams.