Items that do not have offers
Items which are on sale on Amazon has offer listings. However, there can be cases when an item may not have any offers.
Case 1: Item is Unavailable
An item may not have offer listing(s) if it is no more available for sale on Amazon. For e.g. as shown in the image below, the item is unavailable and not for sale anymore on Amazon by any merchant(s)/seller(s).
Case 2: Parent Items
The abstraction of the variations is called the variation parent or a parent item. For example, shirt is a parent item. A shirt that is a specific size and color would be a child of the parent item. Because the parent ASIN is an abstraction, it can't be purchased. Hence, it is not associated with an offer. For more information, refer Variation Parents.
The following snapshot shows how a parent ASINS's information is displayed on Amazon Website. In this example, the price is not shown and the dimension are not selected. The price range of child ASINs are shown instead.