The following is from the mindtools web site:
Leadership literature is full of studies attesting to the consequences of a leader's mood. One such study involved 62 CEOs and their top management teams and it showed that the more upbeat, energetic and enthusiastic the executive team was, the more co-operatively they worked together, and the better the company's business results. The study also showed that the longer a company was managed by an executive team that didn't get along well, the poorer the company's market returns.Perhaps nowhere is a leader's mood more crucial than in the service industry where employees in a bad mood can, without fail, adversely affect business. In one of a multitude of such studies involving 53 sales managers in retail outlets who led groups ranging in size from four to nine members, it was found that when managers themselves were in an upbeat, positive mood, their moods spilled over to their staff, positively affecting the staff's performance and increasing sales. We can all take an inspiration from organizations such as Starbucks who place great value on the importance of creating a positive climate for employees which, in turn, ensures a pleasant customer experience and repeat visits. "We are always focused on our people" is an explicit statement to new recruits on the company's career site.