I just set up two-factor authentication on my backop account and was delighted to see that you all make it easy, not only to set up, but also to manage. Tons of websites say "It's easy to enable two-factor authentication on our site" but they offer nothing more than options to "turn on" or "turn off." But you showed me the QR code and the secret code. You will let me change the code. You will let me specify my own code. If I lose the authenticator, there's a way to reset it. You accept valid codes for longer than the 30 seconds on the authenticator.