The German translations arrive the week before launch. You drop them in, and the checkout button now reads "Zur Kasse gehen und bezahl", cut off halfway through a word. A label that was hardcoded in a modal still says "Close" in English. The order confirmation says "1 Artikel" for every order, however many items are in it.
None of these bugs is hard to fix. They're hard to find, because you can't read German, and by the time the translations arrive there's no time left to look.
Most localisation bugs don't need real translations to show up. They come from the code, not the words, and you can catch them long before a translator is involved. This chapter covers how.