I'm horrible with names. Horrible. Its not because I don't like you, or that your darling face is unmemorable. If your name is Bob, and I call you Juan, its really no reflection on you....just my ADD.
But I do have to say that if you have a weirdo made up name, or name that is normal but spelled phonetically, its not my fault that I can't remember it - that's your deal. Also sometimes I can't remember your name because I already assigned you a "Seinfeld name" for something about you that stood out (Slow Talker, Hawaiian Shirt, Jack o' Lantern Face etc). There's a 50% chance that your Seinfeld name as a good connotation though, no worries.