Jay Chaudhry knows what he's looking for in a hire.

The 66-year-old billionaire has founded five companies altogether, including his most recent, a cybersecurity company called Zscaler. He's currently serving as the CEO of the company, which he says has 7,000 employees. Zscaler's market cap is $25.4 billion as of Tuesday.

When sussing out who to hire, "I look for three things," says Chaudhry. These could be for "a very top-level job," he says, and they could be for "an entry level job."

Here's what he prioritizes.

Passion

The No. 1 most important quality Chaudhry looks for is passion, he says.

"When people are passionate and they have conviction, they automatically work hard," he says. They have that motivation to keep pushing through and solving problems. Plus, he adds, "work is no longer work. They enjoy it, and the results end up being strong."

When it comes to hiring, Chaudhry looks for this by taking note of people's excitement. Passionate people have done their "homework better" ahead of the interview, he says. They also "ask better questions." They're keen to learn and find their place in the company.

Willingness to learn

The second most important quality is a curiosity and willingness to learn.

"In today's world, everything is changing rapidly," says Chaudhry, adding that "the way you work, how you work, where you work — all that is changing." People with a natural curiosity can learn the new ways of working quickly and be up-to-date on how to succeed on the job. They can also help the company move forward using new tech and tools.

To ensure a candidate has this quality, Chaudhry might give them an exercise during the interview process. "They go, they do some research, they come back, they present," he says. Judging by their answer, he can see what they picked up.

Adaptability

The final thing Chaudhry always looks for is adaptability.

"When I hire people from other companies," says Chaudhry, "I tell them, whatever worked for you in your previous company, probably half of it will work here. Half won't because it's a different environment." That's why adaptability matters — every company has its own processes and tools. Chaudhry wants flexible employees who can soak up new information and work anywhere.

To see if his interviewees are adaptable, Chaudhry asks open-ended questions. "Describe to me a situation or project where things weren't going well," he says as an example. "How did you think through the process of saying, 'this is thing is not working, I need to drop it.'" He then asks what changes they made to find success down the line.

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