Supply driven planning
Production planning can be driven by either demand or supply requirements. Demand is the more common of the two methods, because most production activities are performed to meet existing needs.
Sometimes, supply-driven planning is the preferable method. This is particularly true in environments where raw materials enter inventory regardless of existing demand conditions. An example is a company that grows, harvests, and processes produce. In this type of scenario, demand has no impact on the quantity of raw materials that enter inventory, high or low demand does not change the amount of available produce that can be harvested from the fields.
In a demand planning environment, the production planner's primary focus is what needs to be manufactured. Once this is resolved, the next issue is determining what materials must be gathered to complete the necessary production requirements. In a supply-driven environment, these priorities are reversed. With a steady stream of raw materials entering inventory, the production planner's key concern is the current on-hand quantity of these materials and how they can be processed.