In a Mob family, there is a position specifically designed to provide wise counsel: the consigliere. The same holds true in the business world. Warren Buffett may get the headlines, but Charlie Munger is indispensable to his success. Steve Jobs had Steve Wozniak. Bill Gates had Paul Allen. Mark Zuckerberg had Sean Parker to challenge him to expand the vision and then Sheryl Sandberg to execute that vision.