Unlike many other job search mistakes, interview errors tend to be unforgiving. This is the time when first impressions count the most. You need to prepare well and be on your best behavior.

Employers have both positive and negative goals in mind. On the positive side, they want to hire someone who can do the job and add value or benefits to their organization. On the negative side, they are always looking for clues that tell them why they should not hire you.

Make a mistake during the job interview and you may be instantly eliminated from further consideration. Therefore, you must be on your best behavior and avoid the many common mistakes interviewees make.

The following mistakes or errors are frequently cited by employers and job placement experts who have interviewed or worked with hundreds of applicants:

1. Arrives late to the interview.
2. Makes a bad impression in the waiting area.
3. Offers poor and unacceptable excuses for behavior.
4. Presents an unattractive appearance and negative image.
5. Expresses bad, negative, and corrosive attitudes.
6. Engages in inappropriate and unexpected behaviors for an interview situation (shows tattoos, flirts, etc.)
7. Appears somewhat incoherent and unfocused.
8. Is inarticulate and uses poor grammar.
9. Gives short, incomplete, vague, and uncertain answers.
10. Appears ill or has a possible undisclosed medical condition.
11. Volunteers personal information that normally would be illegal or inappropriate to ask.
12. Emits bad or irritating smells.
13. Shows little enthusiasm, drive, or initiative.
14. Lacks confidence and self-esteem.
15. Appears too eager and hungry for the job.
16. Communicates dishonesty or deception.
17. Demonstrates extreme role-playing to the point of being too smooth and superficial.
18. Appears evasive when asked about possible problems with background.
19. Speaks negatively of previous employers and co-workers.
20. Maintains poor eye contact.
21. Offers a limp or overly firm handshake.
22. Comes unprepared and shows little interest in the company.
23. Talks about salary and benefits early in the interview.
24. Is discourteous, ill-mannered, and disrespectful.
25. Appears socially awkward and/or odd.
26. Tells inappropriate jokes and laughs a lot.
27. Talks too much and too fast.
28. Argues with the interviewer.
29. Drops names to impress the interviewer.
30. Appears needy and greedy.
31. Fails to talk about accomplishments.
32. Does not ask questions about the job or employer.
33. Seems too effusive and self-effacing.
34. Appears self-centered rather than employer-centered.
35. Demonstrates poor listening skills.
36. Seems not bright enough for the job.
37. Doesn't know his/her worth and negotiate properly when it comes time to talk about compensation.
38. Closes the interview by just leaving.
39. Fails to schedule another interview and/or ask for the job.
40. Lacks appropriate follow-up skills, such as sending a thank-you note and making phone calls.