Why does everything come down to goals?
Marvin was hardly a goal machine. And had less assists than Lionel.
He offered so much more than basic statistics suggest - runs, passes in key areas, creating space, drawing players to him to create space for others.
If we are using the scouting system/software then it can drill right down to what the club are looking for as a suitable winger. It doesn't always mean goals & assists.
Also, in terms of lack of appearances, I assume the scouting software will also flag that up, meaning there is better chance of a player moving away from a club.
ie has the attributes we're looking for but isn't playing regularly. At that point it's the club's responsibility to physically scout and assess for injury.