It can also help you find your keys.
A place for everything, and everything in its place.
— Benjamin Franklin (and others)
While resetting large, somewhat unpredictable, systems to a known state is critical, the lesson can also be applied to daily life.
When I was in high school I found a small 7.5in. x 4in. wooden box. I had seen stores sell valet trays, but they looked awkward; for me, this little box was sufficient.
Victorian notions of propriety aside, the major benefit of putting things away in a predictable location is the ease with which they are found—and the corresponding savings in time.
As the number of virtual places (e.g., file systems, email) we can "put" stuff increases, this principle becomes more and more relevant.
Inbox Zero for a simple technique for organizing email.
When flying, I thought the purpose of resetting the trays and seats during take takeoff and landing were to put the system in a known state. Apparently, it's more for emergency evacuations and to avoid physical shock.