Inventory is an option that can be enabled or disabled (default) for each item, and is designed to be used where the item is not a single item but rather a collection of consumables.
In that case, the Itefy item is the storage location of those consumable items, and with inventory enabled, you can track every pick, refill, adjustments, and the number of items left.
Inventory is enabled for each relevant item, and is done under item settings.
Item listing by inventory status
You can check for items with a certain inventory status, either above, close to or under threshold, and empty.
Select Items > Find Items from the main menu, or List items from the dashboard shortcut menu. If the search menu to the left isn't visible, click the Search button to the upper left. Then, select Inventory and select the inventory status you want the item result list to match. Then click Search.
Every change of inventory is logged, and is listed with details on either the item page or the inventory changes page.
To see the inventory changes for a certain item only, go to the item page, select the Inventory tab. The inventory tab is only available if inventory is enabled for that item.
To see inventory changes for all items, select Status & Events from the main menu, then Inventory Changes. You can filter on picks, adds or adjustments, and sort by ID, event, amount, previous amount, new amount, item, time (default) or user.