First, a few definitions I pulled from the web:
$this->bbcode_second_pass_quote('', '(')demand) driven inventory system in which materials, parts, sub-assemblies, and support items are delivered just when needed and neither sooner nor later. Its objective is to eliminate product inventories from the supply chain.
Just-In-Time inventory (JIT) is part of a production system whereby a firm vastly reduces inventory from its production processes so that utilization of production inputs and delivery of finished products are accomplished without incurring significant holding costs. While JIT inventory systems are quite attractive for this reason, they are a double-edged sword.
This does not mean to say JIT is implemented without an awareness that removing inventory exposes pre-existing manufacturing issues. This way of working encourages businesses to eliminate inventory that does not compensate for manufacturing process issues, and to constantly improve those processes to require less inventory. Secondly, allowing any stock habituates management to stock keeping. Management may be tempted to keep stock to hide production problems. These problems include backups at work centers, machine reliability, process variability, lack of flexibility of employees and equipment, and inadequate capacity.
In short, the just-in-time inventory system focus is having “the right material, at the right time, at the right place, and in the exact amount”, without the safety net of inventory. The JIT system has broad implications for implementers.
Just-in-time operation leaves suppliers and downstream consumers open to supply shocks and large supply or demand changes. by facilitating the interconnectedness between businesses, JIT inventory systems increases the risk that problems or failures on one end of the production chain might be felt on another end. However, these risks associated with JIT inventory systems may be ameliorated to a certain extent. If in-house production or a supplier buy-out is not a feasible option, firms still have other common-sense ways of preventing these risks.
Just as JIT has many strong points, there are weaknesses as well. "In just-in-time, everything is very interdependent. Everyone relies on everybody else" (Greenberg, 2002). Because of this strong interdependence with JIT, a weakness in the supply chain caused by a JIT weakness can be very costly to all linked in the chain. JIT processes can be risky to certain businesses and vulnerable to the supply chain in situations such as labor strikes, interrupted supply lines, market demand fluctuations, stock outs, lack of communication upstream and downstream in the supply chain and unforeseen production interruptions.
Labor strikes, stock outs, and port lockouts can quickly disrupt an entire supply chain while JIT processes are in place.








