Manchester United haven't exactly had the best record in the January transfer window in recent years.
Last year, with Ralf Rangnick in interim charge, the club failed to bring any new faces into the club as they chose to direct funds towards the summer window and maximise the budget for their next manager to conduct their overhaul. In fairness, that was probably the correct decision given that Erik ten Hag barely put a foot wrong during his summer revamp of United's playing squad.
Christian Eriksen, Tyrell Malacia, Lisandro Martinez, Casemiro and Antony all arrived with Martin Dubravka joining on a loan, which has now been terminated by Premier League rivals Newcastle United, and have all made impressive starts to their careers at Old Trafford. It must be slightly frustrating for Rangnick to watch, though.