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

Which measurement were you seeking?
What diagram label was ambiguous?
What unit information was missing?

Author notes / illustrative keys where applicable:
1. Identify whether the shopper needs body width, overall width, depth, clearance or another measurement for their intended placement. An overall satisfaction answer cannot tell the diagram owner which boundary is missing.
2. Ask which arrow endpoints or labelled surfaces the reader interprets differently. Distinguish the product body from handles, hinges or packaging so a drawing repair addresses the actual ambiguity.
3. Find whether units, rounding or a conversion explanation are absent. Any numbers added to the diagram must come from verified product specifications, not respondent estimates.