Every distribution center requires the functions provided by a warehouse management mystem (WMS) to control inventory movements, from receiving and put-away to picking and packing well as the management of returns.
A WMS can also serve as an important link in the supply chain, including materials management, product allocations and shipment planning. As a plus, a WMS typically offers workforce planning and productivity analysis.
If you do have warehouse and fulfillment functionality in your order management suite, then the decision to acquire a WMS is typically a matter of degree rather than of kind, i.e., how much better will a WMS do the tasks of our order management or ERP system?
Before addressing that question, though, a word of caution: whatever theoretical payback you calculate, you must take into account the challenges you will encounter in implementing and integrating the WMS into your current systems architecture. It is an unfortunate fact of life that getting a WMS to function completely in sync with an order management system, in particular, is fraught with difficulty.
The reason for the dysjuncture is that the logic of any given WMS may not be consistent with the logic of any given order management solution.
Take line-item allocation, for example. There is no universal standard by which allocations of line-items on an order are processed among the various order management systems themselves, so expecting a WMS to automatically match the way your system currently handles this is likely to be unrealistic. At least one major order management system does not do a hard allocation on line-items until they are batched for picking; but if the WMS is doing the batching, then it most likely needs to be modified to hard allocate when the orders are ported to the WMS.
Moreover, not all systems handle the relationship of line-items to orders in the same way, either, which can have a significant impact on the way an order is picked, packed, and shipped.
Worse still, not every mismatch in the logic of the two types of systems can be anticipated in advance. Only careful testing using multiple inventory management scenarios can reveal them all. And some unanticipated modification of either the WMS or the order management system may be required to get both systems singing in key on the same page. Be sure to allow time for this in implementation.
Pay particular attention to how back orders and returns are to be handled between the two systems. If there will be “slips” “between the cup and lip,” these are two major points of vulnerability.