Clearly, the critical element in such processes is accurate information about where the letter (or flat or parcel) is supposed to go. That information starts with an accurate, complete and current address in human-readable form, but must be translated into a barcode if it is to be read by machines. As a result, the increased use of equipment to process mail and the decreased reliance on human knowledge to interpret addresses for sortation and delivery, have combined to make it unwise for mail owners and producers to tolerate less-than-perfect addresses (and thus less-than-perfect barcodes). Once, a person might have intervened to get an incorrectly addressed piece to the intended addressee, but today’s distribution systems rely on the sender’s attention to address accuracy, not the ability of someone downstream to compensate for address shortcomings.