The former CEO of a $34 billion company explains how living in 23 states by the time he was 12 taught him a key business skill

Growing up in a series of about 20 trailer parks across the Midwest, David Novak never envisioned himself as the head of a billion-dollar company.

As the CEO of Yum Brands from 1999 to 2015, Novak turned a PepsiCo spinoff into a global leader in the fast-food industry through the brands KFC, Taco Bell, and Pizza Hut.

When he retired from his position as chairman of Yum in May, he left behind a legacy of 41,000 restaurants across 125 countries and a market capitalization of about $34 billion.

Novak recently visited Business Insider in New York, where we discussed his new book, "O Great One!" and the greatest lessons from his career. He explained that even though he could have never predicted where his life would take him, his unusual childhood provided him with a key skill for becoming an effective leader.

"I don't think I succeeded in spite of my environment, my upbringing," Novak said. "I actually think I succeeded because of my upbringing."

Novak was born in Beeville, Texas, in 1953. His father was a land surveyor for the federal government, which required him and his team to live with their families in trailers, since they would have to pack up and relocate every few months.

By the time Novak's father got a promotion that allowed him to settle down in a house in Kansas City when Novak was in sixth grade, Novak had lived in 23 states.

Anytime they moved, Novak said, his mom reminded him to make friends on the first day of school because if he allowed for a gradual adjustment period, it would be time to leave by the time he finally felt comfortable.

"And I think what this did for me was it forced me to go into situations, size them up really quickly, decide who I wanted to be friends with, who were the good people, who were the necessarily not the best people, and it forced me to probably become more of a people person than other people might become", he told us. "Because it was the only way to really survive."

In his 2007 business memoir "The Education of an Accidental CEO," Novak wrote that this constant relocation and being the "new kid" at school forced him to learn how to overcome fear of rejection at a young age, a skill that he would use in his career when he was made PepsiCo's COO in 1994 and then CEO of Yum.

For example, when he went as CEO to his first Business Council meeting - an annual meeting of 125 of the world's top CEOs - he felt like it was the first day of school all over again. "I quickly sized everyone up and, remembering that they all put their pants on the same way every morning, worked my way around the room," he wrote.