In Mochila reports, we distinguish between two different types of inventory for every item: Available Inventory and Physical Inventory.
On Hand or Physical Inventory is inventory physically in Mochila's warehouse. This includes inventory that is available for to satisfy new fulfillment requests ("Available Inventory") as well as inventory that has already been allocated to satisfy fulfillment requests ("Bound Inventory"). Once a shipment has moved to a status of "shipped" and has a tracking number, the units in that shipment or no longer in inventory.
Available Inventory is inventory that is available to satisfy new fulfillment requests (orders). It is calculated as Physical Inventory less Bound Inventory.
Bound Inventory is inventory that has already been promised to satisfy existing fulfillment requests (orders). Those orders can be shipments that are in progress but have not shipped yet. The may also be orders pending address correction, pending a custom shipment label, or pending LTL approval.
In addition, in certain cases, an order in Waiting for Inventory status may have items for which inventory has been bound to that order as well as items for which there is no Available Inventory to satisfy the order in its entirety. In other words, it is not true that every item in an order in Waiting for Inventory status has no inventory to fulfill that order. Rather, it means that there is at least 1 unit in that order for which there is no Available Inventory to satisfy the entire order.
Reserved Inventory is inventory that is excluded from Available Inventory but that is not allocated to a specific order or fulfillment request. The only way to reserve inventory is to manually set the reserve inventory value. This feature is usually utilized to set aside inventory for future orders that have not yet been transmitted to Mochila.