Because the ballot isn't tied to the voter. It's just recorded as "we mailed out a ballot".
If the person is no longer living at the address, then perfect. They can slip +1 forged ballot in for the candidate of their choice, and no one will show up to dispute it. If there is a dispute, then "Welp, no way to track where it came from and who sent it in illegally, so oh well."
I think it was explained in 2000 Mules.
And it's why getting as many people to show up as possibe is important. The more legit voters, the less room there is in the count for these forged ballots to be slipped in unnoticed.
Because the ballot isn't tied to the voter. It's just recorded as "we mailed out a ballot".
If the person is no longer living at the address, then perfect. They can slip +1 forged ballot in for the candidate of their choice, and no one will show up to dispute it. If there is a dispute, then "Welp, no way to track where it came from and who sent it in illegally, so oh well."
I think it was explained in 2000 Mules.
And it's why getting as many people to show up as possibe is important. The more legit voters, the less room there is in the count for these forged ballots to be slipped in unnoticed.