The unspecific, overreaching sales plan

After backlog, this is generally the second largest producer of unnecessary inventory. It is much more serious, however, because  

When delivery times and internal throughput times are long, sales is required to predict market demands far into the future, which is not feasible. The inaccuracy of these predictions and thus the inventory risk rise exponentially with the distance from the present (Fig. 23). 

With long delivery and throughput times a high inventory risk ispreprogrammed. 

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