I have a product-group consisting of multiple tickets for an event with each ticket choice representing a different time for the event. These are all listed in the product group page, allowing the ability to buy multiple ticket times at once. Each ticket item has its own quantity selector. By default, this selector is set to 0 for each item, and you can increase the quantity of multiple items; this is working as expected. However, if you change your mind on an item that you have increased, the selector will not let you return the quantity value to 0. Additionally, if you select the "-" button to decrease the item quantity, and it is already set to 0, it will change to 1. The only way to reset the quantity value for an item to 0, once it has been changed, is to select it with the cursor and manually type it in. Is this a bug, bad design or user error?