Abilities with forced quickcast or input types
A few abilities in the game you no customization on how to input the ability. Yasuo's Q and R are forced quickcast. WW's Q is I don't even know, some weird version of quickcast. There are others I can't think of off the top of my head.
I still don't use quickcast and idc if it's suboptimal but being unable to configure inputs feels bad and jarring.