Why is it important to close out a flight plan at the end of a flight?

Closing out a flight plan at the end of a flight is crucial primarily because it helps initiate search and rescue operations if necessary. When a flight plan is filed, authorities track the aircraft's expected route and destination. If a flight plan remains open after the aircraft is expected to land, it raises concerns about the aircraft's safety. Authorities may then launch a search and rescue operation to locate the aircraft and ensure the safety of its occupants. This practice enhances overall aviation safety by ensuring timely responses to potential emergencies or mishaps.

The other options, while they touch on relevant aspects of flight operations, do not capture the urgency and necessity of closing a flight plan for the purpose of ensuring safety and initiating timely assistance in case of an unforeseen incident.