The thing which hit me was the (fast) speed at which the dial returns. In a "real" rotary dial there's a governor which controls the speed of the return, thus

The thing which hit me was the (fast) speed at which the dial returns. In a "real" rotary dial there's a governor which controls the speed of the return, thus setting the impulse rate so that the step-by-step switches in the exchange can follow. Every phone tech back in the day would take considerable care to set the governor speed, and would instantly recognise when it was wrong.