While there is currently only a small amount of vote fraud in America, what fraud there is is almost entirely done by mail. Additionally, allowing vote by mail diminishes the psychologically unifying effect of a community coming together to make a decision. Lastly, allowing votes by mail can result in People making a decision and then changing Their Minds while being unable to alter that vote, further unjustly devaluing the fact elections are meant to be a "snapshot" of the electorate on a particular day.