Customers feel satisfied when their orders are fully fulfilled. You play an important role in this and this requires you to do frequent stock update. In the near future, we will be applying fines when your item is out of stock. In addition, we will also apply a fine when you do not inform us in advance that all the requested items are out of stock as we will be wasting resources and time to make a trip to your store.
In order to prevent such situation from happening, do update your stocks frequently.
As a matter of fact, customers are able to add unlimited quantities of a product to the cart, however, the actual allocation will only occur during checkout. In cases where there is insufficient stock, the system will prevent customers from purchasing beyond the available quantity that you have indicated.