Transistor Q-Point

Transister:
My question is,when a transister working as an inverter(switching)why we consider Ic=Iceo=0 and in that case where Q-point will be moved on?
plzz help me.

 

I have changed the title of your thread to make it clearer as to what you are asking.

Dave

 

if a switching device controls the on/off current, can you relate that to a transistors quiescent points where Ic = max and Ic = 0?