Well, all the technology with all the cabling is supposed to disappear invisibly in the utility room and not be located somewhere in the living room or hallway, where the telephone sockets are usually installed.
@musketier: Basically, that’s correct, this also works with normal cordless phones, but then I would need an extra charging station for the phone, which otherwise sits on the base station. And I would prefer to have this in sight to switch such trivial things as the answering machine on and off.
There are certainly bigger "basic" problems when building a house!