A job interview is your chance to place your best foot forward and really wow your potential employer.
According to expert interview coach Barry Drexler, who has conducted over 10,000 interviews, there are three obvious mistakes that you may be making during this time: Bashing your former workplace, placing blame on others and spewing profanity.
Drexler, who has over 30 years of HR experience at notable companies like Lehman Brothers and Lloyds Banking Groups, says that insulting your previous place of employment is the most common out of the three.
"You know you're off on the wrong track when you do that," he tells CNBC Make It . "But people do it."
These insults include disparaging the company, calling one's former boss an offensive name and discussing that annoying thing a former co-worker used to do.
"Trust me, I've seen everything," says Drexler. "Don't insult anybody."
This chance to bash a previous employer usually rears its head when an interviewer asks, "Why are you leaving or why did you leave your past company?"
Often, people see this as a prime opportunity to degrade their former employer with comments like "I didn't get along with my manager" or "that company is going downhill fast."
"No one is going to hire someone that's going to bash their [former] company because then you're going to bash our company too," says the interview expert.
Even if you were fired, Drexler advises that you always speak positively about your previous employer. Tell the interviewer that you had a great career while working there and that you learned a lot, he suggests.
Another common error is blaming others for your mistakes. Again, this often occurs when asked why you're leaving a previous job or when you're asked what you didn't like about a previous employer, says Drexler.
Remarks like "I was let go because my boss had it out for me" or "I was removed from this project because my teammates were lazy" have no place in an interview, says the interview expert.
"Don't ever make it personal with people that you used to work with," he says. "Never say it wasn't my fault, blame people or make excuses."
Finally, and most obvious of all, never curse in an interview. Drexler notes that some people are so used to dropping profanity in their everyday speech that they don't even notice themselves doing it in an interview. Curse words have simply become a part of their vocabulary, he says.
Other times, people drop in "four-letter words" because they are so passionate about what they're saying. For example, "I once had to take over a project that was a total s***show, but I managed to completely turn it around and deliver successful results."
"People know not to [curse]," says Drexler, "but sometimes people care so much they don't realize it."
However, when you do these things, he says, "you lose your integrity."
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