These machines are adjusted to the exact ballot configuration. The line the fields up to fit the printed ballot.
It is possible to miss align the pages intentionally. The fold issue was only done by a machine for the mail in ballots. The others may be folded to get in the ballot box, but they are not creased as cleanly as the machine folded ones.
I know about elections, non-automated. Have run elections for many years.
so in your experience is this a common problem? uncommon? unheard of?