They buy players to fit specific roles, whereas Everton seem to just look at who is out of favour at the big clubs, or has been in form in the months leading up to the window, and then worry about where to fit them in later. For example, since summer 2018, Brands and Silva have signed three wingers that generally start on the left (Richarlison, Bernard and Iwobi), despite only having Walcott, who spent a decade crying about being a misunderstood striker at Arsenal, to play on the right.
There just seems to be an inherent cluelessness to Everton that no amount of spending is able to fix. Like, I think Silva genuinely believed that Calvert-Lewin was going to be the man to lead the line here, based on him giving Sokratis and Mustafi the run around and looking decent once the season was over. The amount of times that these players have got away with creeping up the table when there's nothing left to play for is staggering.