Re: However I wonder why...
I think this familiar design for designers pattern has much simpler underpinnings. It's the default pattern that comes from how we're taught, how specifications are written and how all of us try to simplify the real world with abstraction.
The only consistent cure is to keep the customer in the design conversation at every stage of product planning, implementation and rollout. That is easy to say and, without a Bezos, is difficult to accomplish. And why? Because it's complicated!