Many of us would argue that two of the prime qualities of smart leaders are capacity and passion for learning. People in leadership positions not contributing leadership are learning disabled by management by assumption, opinion and command.
Smart leaders work from good questions that spark new learning, ideas and conversations for others. This doesn't mean they are without vision, principles or opinions. What gives them unique power is the way they use these to craft questions that make a positive difference. They are relentless learners. That's one of the key things that set them apart from other people in leadership positions who provide little or no leadership.