How do dirty voter rolls help steal election?

How do dirty voter rolls help steal election?

Mail ballots that can't be delivered because they have bad adresses or the people they are going to have moved away, accumulate at Post Office completely unsupervised in general areas along with all other undeliverable mail.

Postal and election workers are tempted to steal these through the black markets that are run by "Vote Brokers" who buy these available ballots.

Another problem is the printers see ALL the bad addresses and people who moved away when they prepare the bulk mailing of ballots. Their employees would also be tempted to sell these as well.

Lastly, election workers are sent out without logs to pick up undeliverable ballots and store them back at the election offices.

A single tray of ballots can go for $500 to $2,000 depending on the importance of the race.

How can you tell me with a straight face that low income workers at the elections offices, printers and post office are NOT TEMPTED to steal these unsecured ballots?