Leaders must not only be honest, truthful and knowledgeable, but the very best of them are authentic and consistent as well. If you make a decision, stand behind it across all challenges (both internal and external) and communicate authentically across the enterprise. People you work with must know why you made the choices you have made and they need to know that your principles, integrity and leadership and consistent and non-negotiable.
Be who you are at all times, everyone else is already taken.