I would certainly love this more than typing OTP codes, but what's the recovery method for when I lose my phone? How do you solve the chicken-and-egg of getting

I would certainly love this more than typing OTP codes, but what's the recovery method for when I lose my phone? How do you solve the chicken-and-egg of getting users to install and configure the app in the first place? Maybe this is meant for corporate intranets more than end-users?