1. Talking too much
    1. I think calling them “Interviews” is actually misleading.  The right word should be “Conversations”.  The subject matter wraps around whether or not a match between you and the company you’re in conversation with would benefit both parties.  Don’t feel like each time you get asked a question, it’s your job to blather on & on.  Give them a chance to converse with you – even if they decide to make you an offer despite your wall-of-sound in the conversation, how are you ever going to evaluate the pros & cons of the job if you never gave the other party a chance to talk about the role?
  2. Talking too little
    1. Yup, a contradiction.  Thing is, there’s a fine line.  Talk too much, and you turn people off.  Talk too little, and they think you can’t communicate.  Also, there’s no way their going to be able to evaluate your skill-set unless you can give them some level of detail (some, remember, not tons) around your strengths.
  3. Bad body language
    1. Sounds like one of the punk bands I was in back in my teens.  That said, don’t sit there in a slouch, or with your arms folded across your chest – it sends a major message that you’d rather be somewhere else.  If that’s the case, why the hell are you there?  Make eye contact (just don’t make it creepy), lean forward a little, smile.
  4. Knowing nothing about the company you’re interviewing at
    1. I know, it sounds obvious, but you wouldn’t believe how many people come in and have done zero research – trust me, none of them were asked back.
  5. An attitude
    1. Seriously – you’re not #1.  No one is – there are billions of us on this little rock, and gods know how many more species out there.  If you walk in and act like you’re the cat’s pajamas, don’t expect to get a job.  Who wants to be blamed for hiring an arrogant prick, anyways?
  6. No questions
    1. Every-stinkin’-time a candidate doesn’t have any questions for the person who’s interviewing (conversing?) them, I get that feedback, and it’s always a mark against them.  Questions show curiosity, curiosity shows intelligence, etc…  Also, the interview is your one opportunity to kick the tires on the job a bit – if you take an offer without digging in, and wind up hating the job for reasons you could have uncovered before you accepted, well, shame on you.  
    2.  All that said; keep the questions focused around the job & company – leave benefits, salary, etc to the end.  Kind of like asking for a ring on the second date.
    3. Also, don’t wrap negative context around a question.  Don’t say: “At my last job, my lousy boss was really strict about being on time and I want a more relaxed environment – I can get the job done and he should have seen that, not the fact that I was always the last one in the door”.  Say instead: “What’s the culture like here?  How do you recognize achievement and results?’
  7. Lack of passion
    1. Here’s the thing: passion sells.  I’ve interviewed people who were highly qualified, but seemed just, well, diffident.  Then I’ve met people who maybe needed some training & experience, but who just seemed genuinely excited about the opportunity, life, etc.  Not the annoying, “Hi I’m a morning person, isn’t just everything peachy?  Super nice to meet you!” kind of maniac, but the type who’s interested in everything, and sees opportunity everywhere.  That’s a great hire.
  8. Not asking for the job
    1. Just do it.  Close the suckers – tell them you’re interested, ask what the next step is, etc.  I know it sounds presumptuous, but believe it or not, the interviewer is hoping you’ll close them.  Another way of showing passion & interest.

There are some pretty funny (or scary) examples in this CareerBuilder article on CNN.com.  Good for some laughs…