[bigger_inside]

I've encountered software that just assumes everyone MUST have a middle name. I'm German, I have no middle name. Some software (well, online forms) make this a "hard" assumption, so you have to put an "X" or something in the middle name field; it'll scream otherwise

[xyzelement]

I am an American and have no middle name and I cannot recall any software that forced me to enter one.