Here's a use case:
User enters service request to access some application, and the request is Denied. We have our processes configured to end in a state of Denied, so that when the user looks at their request in the portal they can clearly see that the request was denied, and not just "Resolved." The problem is that all of our Denied requests are still technically open in the system, so we have to go back and resolve them after X time. This also requires us to maintain custom filters and SLA rules which is annoying.
This idea is somewhat related to the feature request to have resolution comments visible to the end user.