Re: @Voland "Because you can"
"In New Brunswick, Canada you are given a paper ballot inside a cardboard shield with the top of the ballot slightly protruding from the shield, you pull out the ballot, mark your choices, put the ballot back in the shield, take it to a vote counting machine slide the protruding end of the ballot into the voting machine which then reads your votes and stores the ballot."
"We do the same here in Michigan. I've been voting in Michigan since the 1996 election and an optically scanned ballot is what I've always used here."
Netflix has a documentary "Hacking Democracy". It details how easily the Optiscan (optical scanner of paper ballots) can be undetectably hacked. It is frightening.