I’m not a designer by title, but I’ve worked closely with UI and UX folks, and the difference becomes obvious once something goes wrong. I’ve used apps that looked beautiful but felt exhausting, and others that weren’t flashy yet just worked. As a user, you don’t separate the two, you just feel the result. That’s why people confuse them. Even when browsing review platforms like https://www.pissedconsumer.com/ , I notice complaints are often about design, when the issue is really flow or logic.