Ballot harvesting tends to create fake votes instead of legit votes.Can you explain how ballot harvesting causes illegal votes?
Someone collects legal sealed ballots and drops them off at the polling place
Going out and gathering ballots is an easy why to cheat. Who knows if the ballots are from the actual voter or a voter that has properly identified himself for herself.
The only way to have a fair and honest election is all vote in one day and in person.