“Just in time” is a terrific idea if your supplier is on the other side of Honshu. Not so much if your supplier is on the other side of the world.
Question I used to ask my students in my systems engineering course: what do safety, security, and reliability have in common?
Answer: Redundancy.
Question I didn’t ask: Who hates redundancy?
Answer: (Left to the reader)
Earl
Q: What do Safety, Security, Reliability and correctly managed Safely Systems represent?
A: Redundancy.
Q: Who hates redundancy?
A: Only a fool who wears a permanent target on his back.
Accountants.
And they detest installing lifts in 300m cape size bulk carriers.
Well summed up from all the previous respondents. Nothing to add here.
“Redundancy is ambiguous because it seems like a waste if nothing unusual happens. Except that something unusual happens—usually.”
Nassim Nicholas Taleb