I recently interviewed two leaders who have each influenced hundreds of millions of people. Over the course of two days, I spoke to Evernote CEO and former Google[x] executive Chris O’Neill, and General Stanley McChrystal, founder of McChrystal Group and the commander of U.S. Forces in the Middle East under Bush and Obama.

O’Neill and McChrystal are known for getting the best out of people. What struck me about these two interviews was that both men, despite different personalities and backgrounds, said something remarkably similar when I asked them about leadership in today’s complex world.

“Before we went to war in Afghanistan, what we should have done is gone whitewater rafting,” McChrystal told me. “And the President, the Vice-President, Secretary of Defense, generals and all that should have gone. And don’t talk about the war; just take beer and go whitewater rafting for a week.”

The general wished his leadership team had spent some quality time learning each other’s personal stories before they went to battle—both in the conference room and the field. That’s because developing trusting personal relationships makes it easier to debate, argue, and dissent in the name of making things better.

“When you approach a problem, you do it on a different level,” McChrystal said.

“Your job as a team is to basically figure out what combination of skills and…