Leadership is a behavior, not a position.
Good leaders solve problems from the perspective of the customer's experience. Bad leaders concern themselves with internal structures or motivations.
Good leaders believe the team they've built is the best measure of their success, and regularly hire people better than themselves. Bad leaders believe short-term outcomes exclusively define their success.
Good leaders are rarely ambivalent on important matters and address conflict head on, by expressing their POV and soliciting the POV of others. Bad leaders keep their opinions to themselves, or worse, use the "meeting after the meeting" to make their true opinions known.
Good leaders make decisions with the available information, valuing experimentation and iteration over the perfect answer. Bad leaders delay progress because they fear making the wrong decision.
Good leaders use their position to support, empower and challenge their colleagues to make them better. Bad leaders feel threatened when they are challenged, and always need to be the smartest person in the room.
Good leaders seek the truth through experimentation, data, and vigorous debate and embrace truth whether it's good news or bad news. Bad leaders only use data when it's convenient.
Good leaders use their experience to recognize patterns, but aren't beholden to the same playbook. Bad leaders run the same playbook regardless of the current facts.
Good leaders have an internal fire that drives them and their teams to be the best, and display grit in the face of adversity. Bad leaders have excuses and confuse effort with results.