Randy Miller, another Amazon former executive, agreed.
"If you start giving rationalizations or excuses, he'll just tear you to shreds," he said. He recalled a meeting with Bezos in which a presenter was not prepared and had a half-baked idea.
"I can remember at one point [Bezos] said, 'I don't know if this is—sheer stupidity or gross incompetence,'" he recalled. "I remember one person said to me, 'Oh my God. I was just praying that I was going to have a heart attack so this would stop.'"
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Bezos may be tough on his employees, but Amazon executives say it's always in service to the company and customers.
"He is harsh on the result, and on the problem, not on the individual," said Nadia Shouraboura, a former executive who was at one point a part of Bezos' inner circle. "He thinks of the result. That there is a disappointed customer, or there is a missed promise."
Miller thinks Bezos' tough management style pushes executives to grow.
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"Those who survive that, do come back and do better," he said. "If you continue to provide the kind of the results that you're supposed to get, the things you're responsible for can grow quite rapidly."
—By CNBC's Michael Beyman