As an example, Let’s say you have many customers waiting to receive back in stock alerts and you restock only very few items of a particular product or variant. In this instance, it is likely that your product will sell out fast leaving some of your customers with an unpleasant experience because the product sold out even before they could see the back-in-stock email alert.

Customers can face a similar unpleasant experience if you process returns on a product that recently went out of stock as the return would trigger a back in stock alert when your inventory changes from 0 to 1.

To avoid this situation, it is ideal that you set up a minimum stock threshold site-wide above which automatic back in stock alerts are sent to customers for their requested product.