1). He/She doesn't know your name. You may know everything about the, but if they can't remember your name, it might be time to reconsider.
2). He/She lives 12 time zones away and everyone involved is terrified of flying.
3). He/She lost their leg in 'Nam. (whereas you weren't even around for Reaganomics)
4). He/She is already married. (Check! Cause all the good ones are taken.)
5). His average annual income can only be divided by itself and zero.
6). His/Her parents were wolves. (and you can never seem to get a hold of them on a full moon)
7). He can't make eye contact through the renaissance fair armour suit he wears anytime he's out of the house.
8). All fourteen of his/her apartment mates agree he/she's the best at halo
9). They can't think of any more legitimate reasons than eight
10). They hope that no one notices that they filled up all the remaining reasons by making a nazi joke and/or a axe murderer joke
11). He/She is an axe murderer
11.5). If by "axe murderer" you meant "some sort of slaughterhouse employee" then by all means go for it. (I bet you did nazi this one coming for the "half")
~Courtesy of Karsten