The UX of a human being is only good if you have a common language. I'm not fluent in Swedish, so for me the ability to read the text on the machine instead of listen to it is a plus. Of course, I can ask the cashier to talk English to me, but that also has some friction to it.
And I only regularly go to two different supermarkets, so once I know their flow, there's nothing new to it. In contrast, humans seem to like to change their interface quite regularly, even between customers...
Ok, I've gone to shop in lots of stores in countries where I do not speak the language, as part of the whole human checkout system there is always (in non street market situations) a machine display that says how much of the local currency I need to give up.
On the other hand I think I may be abnormally sensitive to badly worked out human machine interactions since working out these kinds of interactions is part of my job as a programmer. So when something is poorly thought out I think that I feel it stronger than most people do.
And I only regularly go to two different supermarkets, so once I know their flow, there's nothing new to it. In contrast, humans seem to like to change their interface quite regularly, even between customers...