Everyone has influence. When two or more persons are in relationship, they are influencing each other. Influence can be made more effective through the application of power resources . Collaboration is the willingness to influence, and to be influenced, for the sake of shared cooperative gain. It is the willingness to invest in the relationships and outcomes as an active participant.
Collaboration implies an outcome that is mutually beneficial to the participants.
Leadership requires a direction. An influence relationship between collaborators that maintains status quo or efficiency is not leadership. Leadership is directional. It is work that intends a new vision of change. It is assumed that followers have elected to follow because there is some benefit in the outcome that makes it worth pursuing.