@mawr "Let's say the back-end system throws an error. Tell me a bit about how you would walk through trying to explain to the user what went wrong." (Looking for overly technical explanation to non-technical people, looking for not telling the customer something went wrong).
"Tell me about a time you had to write a solution with incomplete requirements. How did you go about filling in what you didn't know?" (Look for decision-making capability and willingness to be wrong.)