Some of the things I have noticed about them are:
- They understand the principles of agile and Scrum. They understand the source of change comes from the teams, not a process.
- They care about their people. They want to see an end to the cycles of project madness.
- They are willing to grow trust with the teams.
- "Organizational change artist: Guides the organization through agile adoption (and re-adoption).
- Boundary keeper: Reinforces healthy role boundaries both within the team and between the team and the greater organization.
- Value maximizer: Manages the portfolio of projects like a product owner manages a portfolio of user stories, always asking what the highest business value project is now.
- Lean manager: Uses lean thinking to improve organizational flow so that the value teams deliver can be realized without delay.
- Organizational impediment remover: Finds the gritty courage it takes to remove entrenched impediments.
- Team champion: Offers observations from the team boundary and releases the team to reach their fullest potential by truly believing they can.
While this role isn't unconditionally necessary for success in all cases, it is for teams that don't have the authority to overcome organizational inertia that can prevent a team from becoming agile.