Signings which simply haven't been of the right quality or fit. No point spending countless money if there is no foundations behind the signing, i.e. do they fit in with a particular playing style, are they technical enough, physical enough, mentally tough enough.. so many shit signings we have made on this basis.
Bailly, Herrera.. for me are United quality signings but just find themselves in a bad team.. but Zlatan is not a United signing that we would make when we were operating at our best under Fergie.
RB, CB, possible lack of LB if Shaw doesn't crack on, Lack of specialist DM, Lack of specialist wingers full stop, lack of striker at his peak. Huge huge holes in this side in terms of first team quality.
Today people can speak about Mourinho, but for me today we were purely let down by the quality of the players and their mentality. No manager would have magically transformed that result into a win after the start we made. It just killed off the entire game.