Look, I'll make this very very simple...

You get an idea, a theory, a dislike
You go find some statistics that back it up (so no one calls you bad names)
You accidentally forget to include any other statistics that would level the playing field
You stick to your guns and tell everyone else they're clueless
You make yourself look like a prize winning dick (no, thats not a compliment) but you're simply so wrapped up in proving fact where there is none, that you don't even realise it.