Have you ever heard someone say something like "I'm crazy" and it made you grind your teeth? Because I know it makes my skin crawl.
Sometimes, when a friend adds me on MySpace, I find myself reading their About Me, but after I do such, I usually feel nauseous. And do you know why that is? Because it's always the same hyperbolic jargon spewed, usually based around a few ideas:
"I'm smart/funny/cool/insert-other-adjective-along-the-same lines."
"I'm nice, but I'm like totally not the person to mess with."
"I'm a total bitch."
"If you don't like it, go screw."
Now, psychologically, there is something wrong with this, though, it's not made apparent to most. There's nothing wrong with acknowledging a fact about yourself; for example, acknowledging that I am an attractive person.
However, when you dig deep into the psyche of the human mind, you begin to differentiate the two concepts.
There seems to be correlation between what people refer to themselves as and what they attempt to portray. As though their words directly influence how they, themselves act; as though they're trying to convey images of themselves that are not bona fide to the actual package.
To get a grasp of what I'm saying, consider a good book you've read. Normally, the narration will say something like "the crazy fellow" or something along those lines at least once in the book, yes? Perfectly reasonable, yes?
But when you apply this to a real life situation and put such labels upon yourself, all you're doing is writing a character and acting the part. As such, the description you give is moot.
People like this, generally, go out of their way to perform actions that fit the traits they list off of themselves. For example, a girl who claims herself to be a "bitch", will go out of her way to make what she perceives to be a "bitchy" comment to build that aura she so desperately wishes for.
Much like someone who is legitimately crazy does not know they are crazy and, thus, does not refer to themselves as such, someone who is legitimately bitchy, quirky, eccentric, funny, nice, mean, cool, et cetera... doesn't refer to themselves as such.
Don't confuse this with egotism, however. Egotism is a different psychological category as the method actor. An egotist will refer to themselves as "great" or something of that sort, which is another spectrum than one who cites their traits.
A valuable lesson, boys and girls. Stop trying to give yourself an image.