This is, in my opinion, a common misconception about modern day supply chains. JIT is mostly used for the last delivery step, component deliveries for automotive final assembly lines are the best example for this. And even there is a certain buffer, a well planned and monitored one.
All other steps involve buffer stocks and inventories. This inventory is sitting local warehouses for example. Or just dead weight in the various locations. More often than not, this is due to inefficiencies.
That beingsaid, JIT is simply to hard to implement to use it for anything else then the most important parts. and even there only for the very last step, everything else smply has to many variables for JIT to work.
The best example are automotive supply chains that kept running all the time through February.
And stuff like groceries are not run JIT, with the exception of the replenishment of shelves and local stores from a regional warehouse. And that is not true JIT.
All other steps involve buffer stocks and inventories. This inventory is sitting local warehouses for example. Or just dead weight in the various locations. More often than not, this is due to inefficiencies.
That beingsaid, JIT is simply to hard to implement to use it for anything else then the most important parts. and even there only for the very last step, everything else smply has to many variables for JIT to work.
The best example are automotive supply chains that kept running all the time through February.
And stuff like groceries are not run JIT, with the exception of the replenishment of shelves and local stores from a regional warehouse. And that is not true JIT.