This probably varies wildly but in the US (or parts there of) landlines have to work in emergency situations - ie no power. Even if you have a 'phone line' del

This probably varies wildly but in the US (or parts there of) landlines have to work in emergency situations - ie no power. Even if you have a 'phone line' delivered over optical the phone company provides you with an optical network interface device with a battery backup. I keep a landline just for emergency scenarios (also 911 actually knowing where you go if you call them and can't relay your address). Can't get that with no account virtual VOIP services or even rely on the big mobile providers to give you that functionality.