Tell me about a customer request you realized you didn't actually understand. What happened next?

The cheap move is to guess and deliver something plausible; going back looks like not knowing your job. What the candidate did between "request received" and "work started" shows whether they treat clarity as their responsibility or the customer's.

• What did you try on your own before going back to them?
• What did you ask them, and what did the answer change?
• What was the gap between what they said and what they meant?
• What did it change about how you take requests now?

Went back quickly with specific questions rather than one vague "please clarify", checked their own reading back before doing the work, and can name exactly what the request meant versus what it said.

Delivered their best guess and waited, treated the confusion as the customer's failure to write clearly, or the misunderstanding only surfaced after the work was done.