The ballots are damaged before they ever get to the machines. I guess you've never worked at a Board of Elections. At least here, provisional and absentee ballots are delivered in envelopes so that the voter can be checked for valid registration before the vote is counted.
When we open those envelopes, we find ballots that have been folded in strange ways, ones that have had coffee or some other substance spilled on them, etc. We don't even try to put them through the machines. The voters mangle the ballots.
In most cases, it's easy for a person looking at the ballot to see who the voter wanted to choose. The question is whether a state wants to count ballots of people who didn't follow directions.
The polling places make it almost impossible to ruin a ballot, so even stupid people can cast a countable vote there. But there are many ways for people who vote absentee or provisionally to mangle their ballots.
All I saw were KOMO TV video of the ballots that were used at the polling sites. It showed them frayed on the edges and not suitable to run through a counting machine. These ballots had to be hand counted.