Like a lot of regulatory regimes, elections supervision relies in part on after-the-fact enforcement.

This is the point that everyone insists on missing.
The filters are weak. Certain municipalities insist on contaminating the voter rolls with people who have zero, zip, nada, no right to vote. Period, full stop.

Then these same municipalities and interest groups then push back against attempts to understand going in who is casting a ballot legally and who isn't under the insidious guise of "ensuring every vote counts". The unsaid part is...making sure votes that shouldn't count, do.

This is how absurd voting is in some places:

king5.com - King county elections chief printed ballots kshama sawant recall election improve access

One of Seattle's communist city council members survived a recall by (legally) printing ballots at pop-up "voting stations" that her campaign set up. The final margin of victory was...a little over 300 out of 40,000 cast.

The quote about checking ballots for authenticity is hilarious because there's no way to check.

And that's the point. There's no way to really check, so progressives can piously say, There's Nothing To See Here.