What is the last action to occur before the aircraft departs, according to the 10-5-0 rule?

The 10-5-0 rule outlines a sequence of critical actions that take place just before an aircraft's departure. The last action to occur in this sequence is arming the doors, which is designated as the 0-minute mark. Arming the doors is a crucial safety procedure that ensures the emergency exits can be opened quickly in the event of a need to evacuate the aircraft. This action occurs just before pushback and takes place after the boarding is complete and doors are closed.

In contrast, the initial actions of the sequence indicate that boarding must be finished 10 minutes before departure, followed by closing the boarding doors 5 minutes before departure. Thus, the arming of the doors, which is integral to the aircraft's readiness for a safe departure, happens last. This ensures that the cabin crew is prepared for any emergency while transitioning to flight status.