Types of Process Maps

Flows in processes can be forward from the raw material sources to the end-user and reverse from end-users back to the material sources. Forward flows include physical, information, and knowledge. Reverse flows include products returned because the buyer changes his or her mind, defective or thought-to-be defective goods, or products for overhaul and repair. Reverse flows also include payments for goods and services, user feedback about the service and product, and inventory and sales 

Handbook of Supply Chain Management, Second Edition 

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