No one else actually wants him

A pretty compelling reason.

Not only would United have to search long and hard to find a suitor for the midfielder, but they would also have to take a massive loss when selling him.

It would make more financial sense for LVG to keep him at the club until at least the summer and keep his options open.

That way, at least if Fellaini gets a chance to repair his reputation, he will increase his market value.