Why were the Black Order so inconsistent power-wise in Infinity War? I'm specifically referring to Proxima Midnight and Corvus Glave, as the other two seemed balanced enough.

One second they're wiping the floor with top-tier threats like Vision and Scarlet Witch, the next they're getting bodied by Cap, and more notably Falcon and Black Widow, with the latter two having shown difficult fighting regular humans like Rumlow in the past.

My only real theory for this is that Vision was damaged immensely by getting stabbed, which nerfed his power, whereas while Wanda was strong her hand-to-hand experience is very poor. However Corvus was clearly superhuman in strength, as he was jumping the height of buildings and blocking vision's beams.