Strictly speaking, an electric motor is not just a motor, it’s a dual-purpose machine, because it serves not only as an efficient drive unit but also as a generator in deceleration phases.
An electric motor does not have to “get up to speed” before producing its propulsion. It produces its maximum torque from the word go. A combustion engine has to rev up before it can produce torque, whereas an electric motor produces all of its trust as soon as you press down on the accelerator pedal. Also, up to 95 percent of the energy you feed into it gets converted into usable power, whereas a combustion engine, depending on design, can only ever achieve an efficiency of between 35 and 45 percent. But the electric motor’s efficiency is not just a result of the motor itself, it presupposes perfectly matching power electronics which can control the electric motor’s complex processes.