Why is my phone number needed for the doorbell to ring upstairs?

I am moving into a new building, and was recently informed that all tenants must provide their phone numbers to have an active doorbell. I've never heard of this before? But then I've always lived in older buildings. Can someone explain how this works, and why management offices are doing this? What happens if your phone service is disconnected for non-payment and turned back on? Will management have to reprogram everything again?

Does this mean the bell doesn't ring at all? Only the phone? Does this mean all visitors must have my phone number? I don't give all my relatives my home number? lol

Also, when someone rings the bell, will caller ID let me know whether it's the door or a call? Sometimes all this high tech stuff just takes away from privacy.

It's probably one of those systems that doesn't ring a bell, but rings your phone instead. They use them a lot in "exclusive" gated communities vs running lots of wire to individual houses. It doesn't surprise me that a cheapskate landlord or builder would use one of those instead, as they wouldn't have to pay toinstall nor maintain all the wiring. Good news is you can probably have it ring to any phone number you want, IE, a cel phone.

Previous responder is correct. It's a lot cheaper, and about as convenient, to use the commercial telephone system than to install a separate system with dedicated wiring and instruments. Your phone number is not shown to persons at the door. As for caller ID, you will probably see the number of the special line (and the name of the building,or its owner) on your ID set. (If you don't, ask the manager to not block the ID -- you'd like to know if someone is calling from the door.)