In our experience, we disassemble, repair and reassemble objects we can see and touch. Our goal is a repair. However, to repair today vehicles, we must expand our understanding beyond things we can touch, see and use wrenches on. We must apply the technician approach to learning, information gathering and analysis.
As you might suspect, when you reverse the current in an alternating current motor, it takes time for those atoms to get going in the opposite direction. And the amount of time is not necessarily the same as the time it took to get the herd moving properly in the first place.
Occasionally, a technician or service person will ask me, "why not just increase the output by increasing the voltage (the current flow) to the motor?" While that may seem logical, increasing the voltage (in effect, creating an overvoltage situation) will not necessarily boost the output of the device. To understand why, you need to become familiar with a physical characteristic called "hysteresis loss."
Magnetically soft materials, however, tend to be more expensive. The motor manufacturer must find that proper blend of just enough magnetically soft material to do the work required without putting too big a dent in the customer wallet.