Shaving relief
It is common and recommended, when shaving - wet and electric - with the non-active hand, to contract the skin by pulling so that the knife or razor can not move the skin and it does not wrinkle. This creates a flat, stable "work surface" that also prevents cuts.
The same effect can be achieved "one-handed" by simply pumping up the cheeks vigorously.
This also avoids that the left and the right hand partially cross, interfere with each other or the passive hand obstructs the view.
