What's your greatest weakness? If you're trying to find the best employees, it could be just asking that question.
Many of the common questions people ask in job interviews aren't actually that helpful in predicting how well a person will do in a job, experts say. Instead of finding the best job candidates, they end up finding the people who are best at selling themselves in job interviews.
"There are some really good people out there who are not glib, and because they're not glib they're not getting the job," said Priscilla Claman, president of Boston-based consulting firm Career Strategies.
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In general, researchers say the entire job interview process can work against finding the best candidate because it favors people who are sociable, practiced at interviewing and have physical traits such as being tall or having nice teeth.
"What it does is it amplifies all the biases that we have," said Lauren Rivera, an associate professor of management and organizations at Northwestern University's Kellogg School of Management.
Rivera's research has found that employers also tend to hire people they'd like to hang out with.
Of course it's important for employees get along, but Rivera said there's a danger in relying too heavily on that, and not enough on whether the person has the skills to do the job.
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"There are a lot of well-liked people who aren't particularly competent," she said.
Instead of asking cutesy, hypothetical or casual questions, researchers say employers are better off asking every candidate consistent, concrete questions that are directly related to the job the person is going to be doing.
Jeffrey Daum, CEO emeritus at the consulting firm Competency Management, said he urges employers to base their questions on the qualities they see in the best employees they already have. Those may not be the same skills that make people good job interviews, like being extroverted or extremely well spoken.
"If the person isn't going to be a public speaker as the primary aspect of their job, then their ability to communicate in a flowing manner is far less important than the content of what they're communicating to you," Daum said.