If retailers sell products from competing manufacturers in a VMI system,

Vendor-managed inventory transfers the replenishment decision for a retailer's product to the supplier or manufacturer. This can improve coordination when one manufacturer is managing the relevant inventory because it has direct access to downstream demand and inventory information. The problem becomes more complex when several competing manufacturers independently manage inventory for their own products at the same retailer.

Each manufacturer has an incentive to protect the availability and shelf presence of its own products. Because one manufacturer does not fully internalize the inventory-holding consequences created by the other manufacturers, each may replenish more aggressively than would be optimal from the retailer's total-category perspective. The combined outcome is therefore excessive downstream inventory.

This is why inventory at the retailer can be higher than the systemwide optimum , making D correct. The issue can be mitigated by coordinated category management, including assigning one category leader to consider replenishment across competing suppliers rather than allowing each supplier to optimize independently.

This concept directly supports the ACSCP emphasis on inventory management and integrated supply-chain decision making. The exact VMI relationship is also established in standard supply-chain coordination material: competing manufacturers managing their own retailer inventories can produce higher-than-optimal retailer inventory.

Reference Topic: Inventory Management — Vendor-Managed Inventory, Coordination, and Category Management.

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