It's tempting to think the outcome of your next job interview will be determined by the interviewer and not by you. After all, they're the one hiring, not the other way around.

But I flatly reject this. Not only is it categorically false, it's also a self-fulfilling prophecy.

The key to acing a job interview is the same thing that allows sports stars to outperform their opponents, businessmen to defeat rivals, and actors and musicians to ascend to the height of their profession.

It's about performing well under pressure -- which, importantly, is something anyone can learn to do.

What bomb-disposal experts teach us about acing interviews
While some people seem to have an innate -- some might even say "genetic" -- ability to outperform when the pressure is on, the reality is that this is something anyone can acquire.

I was reminded of this recently when reading about a study of military bomb-disposal operatives conducted by Harvard researcher Stanley Rachman in the 1980s. The question he was trying to answer is this: What trait explains the difference between highly decorated bomb-disposal experts and the rank-and-file?

How did Rachman do this? After splitting subjects into the two groups, he compared the operatives' heart rates as they entered the "danger zone" to diffuse a bomb.

Now, just so we're on the same page, here, this is a unique set of individuals. There is no job I can think of where the pressure is more acute than that of diffusing a live bomb, and particularly when you're asked to do so in the midst of a warzone.

It's with this in mind that Rachman's findings are so stunning. Here's how Kevin Dutton describes the results in The Wisdom of Psychopaths: What Saints, Spies, and Serial Killers Can Teach Us About Success (emphasis added):

Whereas the heart rates of all the operatives remained stable, something quite incredible happened with the ones who'd been decorated. Their heart rates actually went down. As soon as they entered the danger zone (or the "launch pad," as one guy I spoke with put it), they assumed a state of cold, meditative focus: a mezzanine level of consciousness in which they became one with the device they were working on.

I don't mean to belabor the point, but this is worth contemplating. Had I entered the "launch pad" to diffuse a bomb, not only would my heart rate be elevated but I would need a change of pants as well. And I don't think I would be alone in that response.

The key to performing well under pressure
At this point, you might be asking what the heart rate of decorated bomb-disposal operatives has to do with acing your next job interview.

The answer, it turns out, is everything.

You see, what separated the men from the boys in Rachman's study was confidence. "The operatives who'd been decorated scored higher on tests of core self-belief than their non-decorated colleagues," Dutton explains.

"It was conviction that made them tick."

And how do you acquire confidence at anything? You get it through experience and preparation.

Why was Bill Gates able to conquer the computer software industry in the face of larger and better financed competitors? He prepared more; he started programming computers even before high school -- that is, when few of his future adversaries had access to the technology.

How did Warren Buffett become the greatest investor of all time? Same reason. Starting at a young age, he was obsessed with business and investing, reading everything he could get his hands on and personally seeking out the experts after exhausting the resources in his local library.

This phenomenon is now known as the "10,000 hour rule," which, as the name implies, states that it takes 10,000 hours to become an expert at something. And, needless it to say, becoming an expert at something gives you confidence in it.

Acing your next job interview
The point here is this: If you want to ace your next job interview, you have to be able to perform under pressure. To perform under pressure, in turn, you need confidence. And to acquire confidence, you need to prepare.

If this seems simple, the good news is that it indeed is. However, the bad news is that it requires initiative and effort on your part.

You need to know about the company and the position. What's the company's history? What's its motto? What are its biggest strengths and weaknesses? What are its priorities right now? What does the position entail? Are there aspects of it that you lack experience in? Are there aspects of it you can completely dominate?

You need to be prepared to answer common interview questions likely to come up. What's your biggest weakness/strength? Why were you fired from a previous job? Aren't you overqualified for the position? Why do you want to work here?

And you need to be ready to perform. An interview is like an audition -- and you can be sure no successful actor goes into an audition without knowing how they want to present themselves and come across to the audience.

In short, the takeaway here is twofold. While the ability to ace your next interview is entirely in your own hands, it takes time and effort on your part to make it happen.

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