We often say we can print what ever size the customer needs.  However, when the customer's artwork falls into standard sizes, it helps both the customer and us.  When print work falls into standard sizes, we most likely already have both printing and finishing templates around those sizes to maximize efficiency.  This allows us to bring the customer the best possible pricing, which is especially true when the paper supply chain is in the dire straights that is is currently in.  When print work falls outside of consistent standards, we can still get the work done for the customer.  However, before we move forward with the order, we will have a conversation to advise the customer of all their options.  Sometimes a change of a quater inch can have significant impact to how the item lays out for production.