Leadership in many cases is a team effort - it can be the board of directors, management group, company division, or a special projects group. One of the reasons that great leadership comes from a team atmosphere is that better decisions will be made.
Groups make better decisions and they can make them just as fast as individuals - follow this link for more That being said, many times a group makes a decision and then the decision is sabotaged by a member of the decision making group.
A key ingredient in group leadership is that the group fully supports the decision once it has been made. When individuals of the group "talk behind the back" or say "I never really agreed", this is a sign of poor group decision making. This also confuses those who will be impacted by the groups decision.
Groups make better decisions, but make sure that the processes and expectations for how the group makes decisions and supports them are very clear. Otherwise, your culture will drown in apathy.