Thank you to @timdenoodle for pointing this incredibly stupid error out.
This is Dave Sharma's full page ad in the Wentworth Courier printed in the days leading up to last Saturday's by-election.
Notice there's no number 10?
Were the Liberals urging an informal vote?
4,911 informal votes were lodged - Kerryn Phelps winning margin was 1,783.
"You must number every box" - unless you followed the no number 10 Liberals ad.
Here's the genius who authorised the ad.