What should an inventory management system do?

Hold one stock position across every location and channel, distinguish on-hand from available to promise, track inbound and in-transit stock, support allocation and reservation rules, handle transfers and returns disposition, and record adjustments with an audit trail. Anything that only counts what is on a shelf is a spreadsheet with a login.

The allocation and reservation capability is what separates the categories. Without it, inventory can be reported accurately and still be sold twice.

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