This job interview tip was 'eye opening' for an ex-Google exec—and helped her hire the best candidates

As a leader at Google for more than a decade, Jenny Wood had a chance to participate "in hundreds of interviews and hiring decisions," she says. And she picked up a few insights along the way.

Wood is sharing some of what she learned in her forthcoming book, "Wild Courage," which will be released on March 25. She does so in her newsletter, Big Small Things, too.

One of the biggest lessons Wood got came "10 years into my career," she says, while she was interviewing a candidate for a leadership role on her team. That's when a mentor at Google told her, "Jenny, the best performance you're ever going to get from somebody is during the interview process, period," she says. "It never gets better. It will only get worse."

Here's how that advice changed her perspective and how she recommends jobseekers carry themselves in interviews.

'It made me more strategic'

Wood's mentor's advice was "eye opening," she says. She realized he was totally right.

If a candidate is "asking about work life balance in the interview," she says as an example, "imagine everything that could become a negotiation down the line." It's not that they shouldn't care about their life outside of work, but the time to ask about it isn't during the interview itself, when they should be focusing on understanding the job.

Going forward, when it came to interviewing candidates, that insight "made me be more discerning," says Wood. Especially at a place like Google that sees some of the best talent in the world applying to its open roles, "it made me more strategic," she says, to "separate the good from the just okay."

'It's worthwhile leading with energy and enthusiasm'

If you're a jobseeker gearing up to do some interviews, remember to bring your best self to the interview because prospective employers are paying attention not just to your work history but to how you carry yourself.

"When you get to the hiring manager," says Wood, "you should act as if you want this job more than anything in the world." Even if you're still figuring out if you want it, give them an indication of the kind of enthusiasm you'll bring if you get the offer and decide you're interested.

"Being a net positive energy contributor is what every manager wants," she says. "And because the interview is a window into [your] future performance, it's worthwhile leading with energy and enthusiasm."

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