This thinking ^ I don't understand.
Let's look at cars. What if consumers demanded "a complete redesign" of cars' main functionality every year or two? Imagine having to re-learn how to drive a car every time you got a new model or different brand?
Consistency with design is a good thing for end users, and good for the stability of the platform. Poor Apple gets it from both ends ... they stick to a proven design, making it really robust, and users complain that it's not changing. They change it, having to start from scratch with refining it, and users complain that it's "buggy". They just can't win.
A totally redesigned iPhone does not cause a user to suddenly need to learn how to use their iPhone again. Were folks confused and lost when the iPhone 4 was released? When the 5 was released? Or the 6? We have had the same form factor now for 3 iterations of the iphone, soon to be 4 with S model. People are lost when the software is redesigned. And with each release if iOS, there is a small learning curve as we rediscover where certain settings are now, or where certain functions now reside.