I think this is a meta-personality flaw, in the sense that I actually like something about myself which a given random unbiased person would call a flaw.
The issue is not so much that I do it with books; there are a lot of words vomited into the ether by a lot of untalented people, and I feel no compunction about writing someone off after a few unremarkable or remarkably bad paragraphs. The problem is that I tend to do it with people as well. I need to hear very little to convince me that someone is not worth my time. It's usually something along the lines of well of course you don't believe in astrology, you're a Libra, or I don't mean to sound like a racist, but...
Don't get me wrong: my conscious brain feels really bad about docking points when someone says that they like Malcolm Gladwell, or Dan Brown, or Lady Gaga. But apparently the rest of my brain doesn't care, and my idiot-profiling is sufficiently useful that my conscious brain shuts up after a token protest, because deep down it's really a sociopath. At least that's the only reason I can come up with.
Even worse: as guilty as it makes me feel, my initial 5-second, 1-minute, 5-minute and 10-minute assessments of whether someone is worth spending time with are pretty accurate. It's the same gut-twisting feeling as when your most awful, cynical prediction of what someone will do is what actually happens.
I feel a little bit like those serial killers/stalkers that you see on Criminal Minds etc; I have this creepy little room in my brain full of stupid things people have said to me. It's like a shrine of idiocy. It's also the one reason I'm thankful that my memory isn't any better than it is, because I would most likely be a much more unpleasant human being if I could remember all of people's failures in excruciating detail.
It's not a misguided notion of superiority that makes me do this (I think). My own glaring failures as a thinker/doer end up in this room as well. There's a kind of macabre scrapbook starting with how I used to think that a coin laundry was a place that one washed coins (in the same scrapbook is a page for a friend that thought a radio doctor was someone who made radios all better...)
My more bureaucratic neurons lump ignorance and culture shock in with stupidity and apathy. The fact that my coworkers all thought that the Jabberwocky was a dance group, and not a poem by Lewis (who?) Carroll --- and the fact that I didn't know that such a dance group existed --- receives the same treatment as another coworker who didn't understand the latent heat of fusion explaining to me that a frozen-solid jug of milk couldn't be left out because the milk that was already melted might get warm.
Again, I feel really, really guilty about this. I don't want to be an elitist jerk. I don't like elitist jerks. ...but quite clearly I don't feel guilty enough to stop being one.
Also, the strange thing about not really having self-esteem problems is that you still begin to wonder (if you're sufficiently introspective) whether you are just as unoriginal and ridiculous and petty as everyone else. So statistically speaking I should probably feel much worse about myself than I do, and feel far more like I'm contributing to the galactic scale of all the the shitty writing in the universe.