Kabore hadn't played in England, so wherever he went it was always going to be a steep learning curve. It also has to be borne in mind that his time at Marseille was disjointed. He only played 90 minutes four times.
McAtee should never have gone back to Sheffield United, though I can understand why he did. That said, the club also left it rather late in finalising its deals this summer, so there was precious little time left to arrange things with other clubs in the top league. Not blaming anyone, just think it becomes really difficult for players to get it right.