I have won the CL and the league twice, but cannot get going in the cup at all. I have a strong squad and can whoopmost teams at my level. But much lesser quality teams beat me time and again in the cup. I think it's the most fiddled comp in the game. It's just too random, doesn't seem to matter what you do.

Whereas the CL and League seem to be more in line with the stats. Weaker teams don't often beat well trained, well maintained, stronger squads. Much more like reality. There will be the odd upset of course, but that cup ... every game seems to be.