Although all 30 points are good, the one below reminded me of a client from years ago. (To read the article go to 30 Things You Should Never Say in a Job Interview.)
23. “What the hell!”
You’d think not swearing is Interviewing 101, but you’d be surprised how often people still do it. Even if your interviewer drops a few S- or F-bombs, you’re better off keeping your language PG.
Some years ago I worked with a Toronto-based headhunter, who has now changed vocations, but who back then recruited candidates for top Canadian employers, among these a well-known furniture store (the one that has the best commercials)! This company doesn't recruit much as turnover is low. It's an awesome place to work!
The headhunter sent a client my way for a strategic resume and cover letter, a young woman who was quite talented in terms of bringing value to the workplace, with quantifiable accomplishments. I gathered these, created her resume and cover letter, and you guessed it, she landed an interview.
And promptly blew this awesome opportunity by swearing in the interview!
My recruiter friend even got a call from the company's hiring manager, wondering what he was thinking, sending over a candidate that clearly did not fit the company's ideal staff profile.
Funny thing was, she dropped no bombs in our conversations, or I would have alerted her that she must not swear in an actual interview, nor did she swear when conversing with my friend the headhunter.
Go figure. Opportunity of a lifetime lost to poor judgement.