Most of the reason interview blunders happen are because of nerves, but some of them are just out of sheer stupidity.

Careerbuilder.com recently released findings from a survey of 3,000 hiring managers and human resource professionals about some of the most unbelievable (we'll call them stupid) interview blunders.

• One candidate answered their cell phone then asked the interviewer to leave their own office because the conversation was "private."
• A man smelled his armpits on the way into the interview room.
• A woman who had applied for an accounting position said she was a "people person" not a "numbers person."
• An interviewee asked for a ride home following the interview.
• A man said he was fired from his last job for beating up his boss.

In job interviews as in life, it's all about how you play your cards. Good rule of thumb: Don't check your common sense at the door.