All EPL teams have one or two challenges they're experiencing, but United problem is an open one which is easily discussed outside these walls. The Glazers family are the core problem of Manchester United, everything trembling in Old Trafford. United in shackles and finding it really difficult to win games because there's alot to comprehend in the club. They're incompetent of managing the Red Devils, having no clue on how to elevate the team, not bringing in sufficient monetary budgets to execute good plans for the club, as if it's more comparable to an average club.
The Glazers have been unfairly used as a scapegoat for quite sometime now, the Glazers might have failed especially in the aspect of infrastructure, but i disagree that they haven't invested money in buying players. Manchester United have been buying expensive players for a long time now, just that most of them didn't perform well, in other words, you can say that they have been spending money on the wrong players.
Having said that, the Glazers should not take all the blame, the manager, players are other staffs should be responsible for United's poor performances as well, enough of the Glazers being used as a scapegoat for bad performances of the team.