Electric motors can deliver tremendous amounts of torque, in a smooth flow. No shock to the driveline.
ICE vehicles deliver not only tremendous shock, due to driveline tolerances, but also constant pulses of shocks due to the individual explosions in each cylinder. Each shift also releases and then reapplies the torque.
ICE vehicles have lots of shock, as it goes from 0 torque to max torque. At zero torque there is always some play in the transmission (each gear) the drive shaft, the gears in the differential, the half shafts and various U bolts. In an electric system all these systems can be easily and simply pre-loaded with micro torque, so when the pedal is pressed all the torque is delivered smoothly, with no impact.
Easy to see. You put an ICE vehicle up on a jack and wiggle the rear tire back and forth. You can feel the amount of driveline slack in your hands.
Worst possible case was when we were kids. We would put our car into reverse and go backwards. Then suddenly shift into drive and we could snap the rear tires enough to lay a nice patch. Pretty fun, but often disasterous.
You can still see the same thing when an ICE car lines up at the drags. If they do not preload the driveline with a little torque, often drivelines will break on the launch. The second most frequent cause of driveline breakage or a drag car going off line is when it violently shifts into second gear. Those lower gears multiply the torque to get the car underway, and the stresses can be violent.
By comparison, a single speed EV will just smoothly launch down the track with smooth acceleration and little breaking of traction.
