what really is a project team?

What really a project team describes about how we lead, manage, motivate the team. No matter how big is the project if we don't have an optimist team members, the project will not be succeeded. The motivation and encouragement that a project manager has to give the team member or what if it doesn't reach to members. The energy flow should be ideal and progressive, then only we will be able to cover things which has to be done.