For most events, Robin will try to update the event organizer's calendar when meetings end early, extend, etc. This has a few nice benefits over just updating the room resource's version. Here's an average use case:
Alice schedules a 60 minute meeting on her calendar and invites the conference room. By some miracle, it ends 30 minutes early. She presses "End Meeting" on the room display on her way out of the room. Robin adjusts her calendar event to end at the current time, which then updates everyone's (including the conference room) schedule.
By adjusting the organizer's event instead of just the room's copy, everyone invited will also get the update. This mean's Alice's calendar will always reflect her actual availability for co-workers. You can imagine a similar scenario for clearing everyone's schedules when a meeting is canceled due to no-shows.
For events booked through Robin (i.e. room displays, web, mobile apps) the booking user will be the organizer on your behalf and these permissions are given by default. If Robin is unable to edit the organizer's event for some reason, it will fall back to updating the room calendar's version.
Cascading changes in action
This is easy to visualize using Google Calendar. In this case we just edit the room's event and nobody else is updated:
But if you update the organizer's version it changes everywhere:
As we continue to develop user-to-room and user-to-user scheduling tools, this permission becomes more and more important to successfully scheduling without creating confusing workflows for your users.