Great leaders have strong opinions, loosely held. They think for themselves, speak with conviction, and invite others to do the same. They don’t fear being wrong; they welcome it, knowing that changing your mind in light of better insight isn’t weakness but intelligence. If you hire world-class people but don’t create an environment that encourages them to bring questions, ideas, and thoughts that challenge yours, you are leaving a lot on the table (and very likely to find those people won’t last long). But while great leaders adapt their views, they also stay true to their core values and refuse to compromise their principles.