Paysa used IBM's supercomputer Watson to determine the top 11 most cautious tech leaders in Silicon Valley and around the U.S., scoring them on a a scale from 0 (least cautious) to 1.0 (most cautious).

However, it's one of the top personality traits among tech leaders, according to a recent study by job search firm Paysa using IBM data. And the most cautious is apparently SpaceX CEO Elon Musk .

When you think about qualities that make a successful Silicon Valley CEO , the first thing that comes to mind isn't usually "cautious."

While Musk scored an impressive 0.96, Cisco CEO Chuck Robbins was very close with a score of 0.95. Microsoft CEO Satya Nadella and Oracle's Larry Ellison followed with scores of 0.91. The least cautious CEOs are Alphabet's Larry Page and Facebook's Mark Zuckerberg, who are tied at 0.73.

To arrive at these results, Paysa "gathered speeches, essays, books, the transcripts of interviews and other forms of communication produced by those highlighted above. After we'd obtained over 2,500 words, we fed these through the Watson Personality Insights API."

"Personality Insights extracts personality characteristics based on how a person writes," according to IBM Watson's website. "You can use the service to match individuals to other individuals, opportunities, and products, or tailor their experience with personalized messaging and recommendations."

It might be surprising that Musk is considered the most cautious CEO in tech, especially given his moonshot ideas and companies. It's important, however, for leaders like the SpaceX founder to take calculated risks (which is something self-made billionaire Richard Branson swears by) versus ones that are simply crazy.

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See also: Mark Zuckerberg, Satya Nadella and Bill Gates share this crucial personality trait for achieving success