Of course it is easier for them to cheat. That is why some states, probably swing states like in 2020, are saying it may take weeks to count all the votes. Maybe that is because dead people have a really hard time getting to the drop boxes.
That’s one reason that in-person voting is so much more preferred. Anytime someone else other than the voter handles ballots, that takes time, procedures, rules and potential mistakes. If a voter takes his own ballot, filled out at the voting station, and deposits it into the counting scanner, it’s done. The vote is ready to be transmitted to the election office, and eventually, the secretary of state.
In person voting is exceedingly efficient and results are readily available.