The reality of firing is not that of capability. It’s rarely that. 
It’s that of a value mismatch. The value that is being added is lesser than expected or the strengths possessed are not valued enough. 

The same value can be significant someplace else. And it usually is. 

The hard part about firing then becomes realizing this fact. And thus still maintaining respect for the individual. 

I have personally fired 27 individuals in my life. 

Not one of them would refuse to help me if I called them one day for help. 

Most would say that the firing, though painful at that stage, was a wise decision eventually. 

They were told, with respect, of how the mismatch will not work out. For both parties involved. 

That it is best for both to move on. 

Maintaining respect for the opposite side, when the side has not delivered, is a hard thing to do. 

It is also the right thing to do. 

Respect is never situational.