As per industry trade customs, overruns and underruns not exceeding 10% of the quantity ordered shall constitute an acceptable delivery. According to these standards, 4,500 pieces on a 5,000 order is an acceptable order. Although such a scenario falls within an acceptable delivery, it is never the case at 4OVER4.COM. We understand that when you order 1000 cards, you would like to receive 1000 cards. The overwhelming majority of the time, we ship you more than you ordered free of charge. All orders are "counted" on an electronic counting scale before shipping therefore rarely, if ever, we may ship slightly fewer pieces than you ordered due to the inherent nature of the printing process. If you plan to send your print job to a mail house, we recommend that you either order a greater quantity or inform a member of our team about your situation. Please keep in mind that if you are sending your postcards to a mail house or fulfillment center.