Complacency is the kiss of death in business and in life. That's why Jeff Bezos recommends using fear to drive work ethic and innovative-thinking — even when things are going well.

"I constantly remind our employees to be afraid, to wake up every morning terrified," the Amazon founder wrote in a 1999 shareholder letter. "Our customers have made our business what it is," he continued, "and we consider them to be loyal to us – right up until the second that someone else offers them a better service."

For Amazon to remain competitive in the future, employees needed to be scared of no longer being the best and commit to "constant improvement, experimentation and innovation in every initiative."

Using fear as a motivator is a strategy that has also worked well for others, including Tim Ferris.

Ferris, the best-selling author and podcast host, encourages fear-setting, an exercise where he writes down his fears, what could happen as a result of that fear, and how he'll prevent that worst-case scenario. He says his biggest wins have been connected to this process that helped condition himself to fail in order to find success.