We have seen a number of customers who improved their overall signup rates by adding OAuth as an option. The effect is even more pronounced on mobile and consumer web.
Most people do not log out of Facebook and Google on their devices, so they do not have to sign-in. They just click "Facebook" then "Approve." That's much easier than filling out your email and password -- particularly on a mobile device.
Most people do not log out of Facebook and Google on their devices, so they do not have to sign-in. They just click "Facebook" then "Approve." That's much easier than filling out your email and password -- particularly on a mobile device.