If nothing was unclear or difficult, say so. Skip questions about steps you did not experience; use not applicable where appropriate.

Which change affected your experience?
What previous feature did you expect?
What should be explained before returning?

Author notes / illustrative keys where applicable:
1. Use this answer to locate the part of the experience that needs explanation. The example issue to investigate is: returning attendees assume last year's room layout still applies.
2. Expected earlier features reveal where repeat visitors may rely on outdated event information. Explain confirmed changes before arrival, while distinguishing a remembered preference from a commitment to repeat previous arrangements.
3. Turn the requested improvement into a testable next step. One illustrative action is: highlight verified venue and schedule changes.