The biggest use case is that we needed something to support our password-change policy on mobile devices. It is easy and straightforward for our in-house employees to change their login credentials but it is different for our mobile users. This is in part because some of our mobile users never come back into the office.
The specific challenge that we needed to solve was first providing the ability for mobile users to change passwords on their laptops, but in addition, have those credentials cached so that they could then use them remotely.