Suzy Welch: This is the one thing you should always say in a job interview

Every job candidate knows how to start a job interview — on time, with a smile and a firm handshake. But it's less clear how to end a job interview in a way that makes you stand out from the competition.

According to bestselling management author and CNBC contributor Suzy Welch, the last few minutes of a job interview can make or break your chances of getting the job. And there's something you can say to ensure that you're memorable — in a good way.

After you've made your case and the hiring manager concludes the interview, don't just say "thank you" and leave.

Before you exit, be sure to say: "I really want this job."

While you may worry that being so honest sounds desperate or awkward, Welch says the rewards are worth the risk.

The statement demonstrates three character traits hiring managers are looking for:

"Coming right out and saying 'I really want this job' shows a refreshing level of sincerity," she says. "It always strikes people the right way."

There's a simple reason for this. Going off-script shows that you're authentic, a quality Welch notes is "in very short supply in the world."

In fact, research suggests that for qualified and experienced candidates, demonstrating candor in interviews can pay off.

Firmly expressing that you want a job also requires drawing on your personal strength.

"The person hearing it knows it's difficult to say," Welch says. "They know it takes moxie, and they'll remember that."

Managers appreciate employees who show courage at work, whether it's reliably taking initiative or speaking up when something is wrong.

Admitting how much you want the job shows that you're not prideful or overly confident.

"This is your moment to acknowledge, 'You're the buyer. I'm the seller. I get that,'" Welch says.

It communicates to the manager that you know that ultimately, they're the one who makes the decision. And that shows you have respect.

"Make your case. Give it your all," Welch says. "And somewhere near the end of the process, make sure they know how you really feel."

Suzy Welch is the co-founder of the Jack Welch Management Institute and a noted business journalist, TV commentator and public speaker.

More from Suzy Welch:

Like this story? Like CNBC Make It on Facebook.