I was told that according to a supply chain exec at a major US retailer, saving 1 day in supply chain lag time would save said company $100MM per year.
Wasn't that turned upside down by the Toyota way of doing it? I remember hearing an episode of This American Life about it. The difference being that it saves more money to fix the problem right the first time then continue the line rather than continuing the line at all cost and fixing later.
This particular ford plant gets engines Just In Time from the foundry ~100km away, using a highway that has frequent traffic jams.
It was found that when a truck load of engines was late, the most cost effective thing to do was to crush the brand new engine-less cars, and crush the engines when they arrived rather than either stop the line, or try to shuffle the cars & engines in at a later time. It was mind-boggling, but the numbers were run many times in many different ways and it was true.
The key to the Toyota method is that over time, it results in fewer line stoppages overall, because real or potential problems are identified quickly.
If a bolt is hard to thread, but you never stop the line, you're going to get a lot of crossthreaded bolts. But if you stop the line for every crossthreaded bolt, the company will very quickly realize they need to spec or design a better bolt.
So, the "anyone can stop the line" mindset only works in the context of a management philosophy that values continuous improvement.
I was told that according to a supply chain exec at a major US retailer, saving 1 day in supply chain lag time would save said company $100MM per year.