Buck Gizmo -Volts vs Amps ? UPDATED

So the CV- only gizmo always does its max amps output within the watts, while the CV/CC gizmos can output fewer than max amps and less than input voltage. Where do the remaining not- being-output, input watts go?

This leaves some watts left over, so you can slowly raise voltage while the less- than- max amps are held constant? Limit being when you run out of watts?