Would not characterize it as an error, but rather as damage. Something else going on there that's likely unrelated to the original foundry. Markings are stamped into an aluminum pattern, so there is no process whereby lettering is lined up to be stamped (impossible, actually) or incised into the pan itself. The indistinct lettering here suggests maybe the pan was copied from another pan used for a pattern. Can't really tell without seeing cooking surface. As we always say here, close-ups are more often a hindrance than a help. Even actual "errors" are not one of a kind since the error was in a pattern that made potentially thousands of pieces. Some Wagner National skillets marked "NATONAL" and Griswold DOs marked "DUTOH OVEN" are two that come to mind.