To avoid that, you need a raw material inventory. But how large should it be? The principle to be applied here is that you should have enough to cover your consumption rate for the length of time it takes to replace your raw material.
A common rule we should always try to heed is to detect and fix any problem in a production process at the lowest-value stage possible.
The limiting step here should clearly be obtaining a conviction. The construction cost of a jail cell even today is only some $80k. This, plus the $10-$20k it costs to keep a person in kail for a year, is a small amount compared to the million dollars required to secure a conviction. Not to jail a criminal in whom society has invested over a million dollars for lack of an $80k jail cell clearly misuses society’s total investment in the criminal justice system. And this happens because we permit the wrong step (the availability of jail cells) to limit the overall process.
In fact, if indicators are put in place, the competitive spirit engendered frequently has an electrifying effect on the motivation each group brings to its work, along with a parallel improvement in performance.