[tawm]

I think the question is about gate charge.

[amelius]

And I guess gate capacitance may cause signal-delays.

[magicalhippo]

Not just delays. Being able to drive a transistor fast can be important for reducing power dissipation. That is, for switching one wants the transistor to spend the least amount of time in the non-saturated (linear) region where it acts as a resistor.

[zwieback]

Yes, that's what I was wondering about.