When will ring central be going to a more secure Two Factor Authentication method that uses SMS as the authentication code endpoint? With a number of email accounts being subjected to numerous phishing scams, sending codes to an email address is a far less secure method then sending codes via SMS/Texting. Plus it is faster method then email or a phone call
I agree with the Google Authenticator but not everyone has it and that requires you to install it, set it up and so on. SMS is just a little easier yet still secure. Oh and those number expire in SMS as well so you have to be timely when you get them. And text is generally fast.
Getting codes via SMS for 2 factor authentication is being discouraged by the security community. Here's some examples: https://krebsonsecurity.com/tag/2fa/ I would stick to apps like Authy/Google Authenticator and a FIDO based physical key like yubikey or Google's Titan key.