Just a thought, from RESULTS ORIENTED
As a leader, do you exhibit a good mood or a bad mood. And does it matter?
Well, this article shows that it does matter. The team responds to the mood of the leader.

A good mood will make people more collaborative.Collaboration is a necessity in today's environment. There is very little that can be accomplished alone. So as a leader, you need to exude good humor. That way the team will work together.

A bad mood makes people try harder on their individual tasks. So if there are specific tasks that are not on track, then the study shows that the leader should express their bad mood. The work will progress with greater urgency

The study also showed that if the project is working well, then the leader is happy. But you probably didn't need a survey to know that.

As always, when dealing with people, honesty of emotion is vital. So with that caveat.... always try to be in a good mood.

Source: Article 'The Contagious Leader' by Stephane Cote, Thomas Sy & Richard Saavedra, Rotman Magazine, Winter 2006