Just In Time

Note: If you are interested in Just In Time Compilation; go there. This page discusses the Just In Time business management strategy; which is a completely different topic (though the two topics do share some underlying philosophy in common)

Just In Time is a procurement oriented application of a strategy to minimize Logistic Delay and minimize the size of inventory in manufacturing organizations. The idea is to use trusted suppliers and contract them to deliver exactly the right amount of ready-to-go parts, tested, etc. exactly when you need them ... i.e. just in time! This lets you meet all your production goals in a timely manner without experiencing delays and carrying inventory.

Good idea in principle -- in practice it is hard to achieve except when quantities are very high. In practice it means that the vendors maintain your inventory which merely passes the cost back down the food chain to the suppliers which either squeezes their profits or they charge more for the extra service. On net, however, it is a money saver. It is more difficult to apply in R&D or product development where quantities are all small and the outcome of many tasks is uncertain. --Ray Schneider


The old model that Just In Time Inventory Management replaces is...

Economic Order Quantity:
"What quantity should we order, given the known lag time, to ensure that we don't run out, and to overcome the costs of placing and paying for the order?"

EOQ is bad for both customer and supplier: Suppliers get spiked with unpredictable orders, and customers don't have a reliable supply.

Just In Time Inventory Management solves this problem by going to a "continuous" inventory supply process, eliminating the spikes of ordering and delivering in bulk. This reduces the inventory that supplier and customer have to carry. And the supplier benefits from more predictable demand.

(The actual business benefits of this approach may be obscured by the catchy "Just In Time" visualization -- which may exist just to distract top management enough that they buy into it. ;-)


We often refer to our work on Chrysler Comprehensive Compensation as Just In Time Programming. Since we Do The Simplest Thing That Could Possibly Work, features that might be needed later aren't done until later, when they are actually needed. Often they aren't needed at all, as described in You Arent Gonna Need It.


Picture this method in use in building the Space Elevator. Where the Simplest Thing That Could Possibly Work is completed Just In Time with no features missing(matching You Are Gonna Need It)at that precise instant when connection is made of the previously independent modules with matching opposite force dependencies. (No sooner than 2053, since people haven't stopped laughing yet!)




See original on c2.com