If my 190 suddenly has a roll rate like a P-38, I look to see which wing or aileron is broken.
If pitch is sloppy, I'm betting it is the elevators.
Yaw control crap? Rudder
White/gray smoke? Fuel or coolant.
Plane suddenly falls out of sky? Tailfeathers
Plane tilts when dropping flaps? hmmmmm....
Cartwheel on the runway? gear...
Oil all over windscreen? I think that one is obvious.
Mapping a button on the joystick makes it about as simple as it can get if you really need it on.