Comment by dmurray

There's a mismatch with reality, because there really is a delay between a registration being received and someone starting to work on it.

This sounds like a beginner PM's plan for a task management system. Just make the status DONE or NOT_DONE, tasks are always done roughly instantly, stop adding complications with your intermediate states! Later this leads to bugs or at least poor UX because tasks don't finish instantly, and someone is convinced to add IN_PROGRESS. Eventually we add CANCELLED and FAILED and UP_FOR_RETRY and, if we're unlucky, a hundred more states. The benefit of those depends on the application but there's always a benefit in representing the three states instead of two.