[someweirdperson]

> Is it there so that when the finger stop moves, it registers the number?

No. Moving to the stop is just to wind up the mechanism up to a defined point. After being released the dial turns back at a defined speed, and creates a number short on-hook spikes, depending on far it has been wound up - the number to be dialed.

It's possible to quickly tap the hook to dial a number, too. It's easy for low numbers, but the dial helps the slow ones of us to tap exactly 9 clicks in the defined time to dial a 9.

No idea if that un-smartphone works exactly like the real thing.