Every once in a while a barrista is going to forget to you wanted soy in your triple venti no-foam soy latte instead of whole milk. They're serving a thousand drinks a day and the impact of getting the order wrong is tiny.

They're still going to apologize to the customer who got the wrong drink. Because sometimes mistakes are acceptable, expected on occassion, and still worth apologizing for when they happen. I don't always say sorry when I do something wrong, I sometimes say sorry when what I've done has a bad impact on someone.