Manchester United paid a fee of €40m to sign the Dutch midfielder from Ajax last summer but so far, he has made just one Premier League start for the club.
Ole Gunnar Solskjaer recently defended his limited use of the midfielder and insisted that with time he will become more important once he gets goes through his adaptation period in England.
But Bosz indicated that Manchester United did not need a player such as Van de Beek in the summer when they already had the best number ten in world football in Bruno Fernandes.
The Dutchman managed the midfielder at Ajax and indicated that while Van de Beek can play different roles, he does not suit the kind of football Manchester United want to play.
Bosz told The Athletic: “Some players take more time than others, in all leagues.
“But I do question why Manchester United brought Donny in. They already have the best player in the league in that position: Bruno Fernandes.
“There is no space in their midfield for another No 10.
“Donny can play as a No 6, but it must be a compact pitch.
“If it becomes a big pitch, it’s not his game.”
Van de Beek is said to be happy at Manchester United but wants to play more football in the latter half of the season.