The agile ideal is for a team to be composed of equals, peers who neither direct each other nor oversee each other, but who work collectively toward a common goal. Team members are self-directing in the sense that they, seeing the goals of the team, choose to work on things for which they are most capable. Since many teams start from a traditionally managed, externally directed world, the journey toward this idea takes time and adjustment for everyone involved. A team typically cannot become instantaneously self-directing.
Typically the journey is assisted and facilitated by a coach who helps the team learn new techniques and overcome barriers. The very existence of the coach suggests that the team is not wholly self-directing, at least not yet; the coach will naturally provide some direction to team members during the learning process. The degree to which the coach will "direct" depends on the progress the team has made toward becoming truly agile.
A typical problem is reflected in a recent question raised by a client. We recommended use of a particular newer framework (SOAJ) in place of the Hibernate/Spring framework familiar to the team, based on our understanding of the goals of the project and the skills of the team; in short, the new framework would reduce coding and increase code quality while improving performance. Some team members felt more comfortable with their familiar framework, however, and the team was divided on the use of the new framework. If the team is self-directing and self-organizing, who makes the decision in the event of a split decision?
It often falls to the agile coach to make these decisions. The coach generally has greater experience and is better equipped to make the choice when the team lacks experience. Coaches must be careful not to become dictators, however benevolent, and teams must take care not to become over-reliant on the coach. Over time, the incidence of coach intervention should decrease as the team gains experience and confidence.
Coaching is more than mere facilitating new practices: there is always an element of leadership in successful coaching engagements. Teams learn best by doing, and the coach must lead by doing as well. Over time, team members step forward and the coach steps back until, one day, the team is leading and directing itself. At first, however, the coach takes more of a directing role.