Garry Kasparov was the world’s top chess player for 20 years. Trained in the Soviet system, he’s become a mentor to younger players, an ardent promoter of the sport, and a vocal critic of corruption in both the World Chess Federation and the Russian government.

HBR: What can people in business learn from the best chess players?

Kasparov: In chess, soccer, baseball, business, politics—God forbid, war—we make decisions. Some are good, some not so good. The way to improve is to look back and analyze them. Many people think that if something worked yesterday and is still working today, it will work tomorrow. That’s wrong, because people on the losing side will come up with a new strategy. I stayed on top for 20 years because I knew that even if you win, there are things to learn. There’s no such thing as a perfect game. Not resting on your laurels is a very important lesson.