- Dressing inappropriately according to the workplace
- Arriving late for the interview
- Forgetting the name of the interviewer
- Your mouth stinks (might be you were smoking a cigarette outside office premises just before interview time, another reason to adopt a portable vaporizer that smells nice.)
- Lack of a good preparation
- Wearing shades in the office
- Applying lots of deodorant or perfume
- Wearing a Bluetooth earpiece
- Speaking rudely to the receptionist or interviewer
- Staring regularly at a receptionist
- Poor communication skills
- Lack of research of the employer in advance
- Forgetting to bring a copy of your resume
- Bringing a photocopy of your resume rather than the printed version
- Complaining that you are kept waiting
- Taking the seat before your interviewer
- Forgetting what you have written on the resume
- Failing to highlight your achievement
- Inappropriate body language
- Failing to listen carefully what interviewer is asking
- Not asking for clarification when you don't understand the question
- Not being prepared with the appropriate questions to ask in the end of the interview
- Bad mouthing about your past employers
- Lying about your experience, skills and knowledge
- Talking too much or very less
- Interrupting the interviewer in between of a conversation
- Don't tell personal stories when asked "tell me about yourself"
- Too early to ask about the salary
- Being unprofessional and non-serious while giving the interview
- Not asking about the next interviewing process
- Attending calls in an interview
- Failure to show an interest in the job
- Be honest and humble - Don't be over-confident
- Failing to show enthusiasm
- Asking for job benefits very soon
- Not able to convince why you are the best person for this job
- Not preparing yourself to answer the regular questions
- Not able to match the communication style of your interviewer
- Yawning and sitting in a relaxed position
- Bringing your parents or friends in an interview
- Chewing gum or tobacco
- Playing with your pen, pencils or paperweight
- Bitting your nails
- Always saying "hmmm", "you know", "actually", "basically"
- Sounding like you know-it-all
- Offering to shake hands first
- Shaking hands firmly or too weakly like a formality
- Not able to make eye-contact or continuously making eye-contact with the interviewer
- Becoming over defensive or angry
- Not able to hide your nervousness
- Explaining too much about why you want to left your last job
- Sounding die-hard to get the job
- Not asking the job details
- Checking the time again and again
- Forget to switch off the mobile or put it in silent mode
- Sounding like that you are rehearsed too much (copybook answers)
- Last but not the least, following up after the interview

Finally, even if you were not able to make up the interview, don't take it to heart. I think everyone in his or her life has been failed one or twice in an interview including me. So learn from your mistakes and look forward to the next opportunity.