Is the takeoff power always maximum?
Takeoff power is almost never maximum engine power.


Maximum power affects engine life as it brings significant wear to the engine. IIRC, if max power is used on takeoff, the crew must log an entry in the logbook to notify maintenance.
Turbo-fans produce a lot of power. If you require max power to takeoff, you better double-check your numbers, or you're operating with a pretty narrow margin.


The reality is the reverse: airlines love to do low power takeoffs, and they avoid a high power takeoff as much as practical. Occasionally, a condition such as high ambient temperature (resulting in high pressure altitude), heavy load, obstacle on departure path may demand a max power takeoff. Possible wind shear may also prompt the crew to select a higher takeoff power.