When running a team, it's important to be able to control the work of your team. This way you can prioritize the clients that bring you more revenue.
With Manager Role, you are able to adjust the project priorities of your team members. When that happens, regardless of project priority they have (by default "Normal") you can adjust which tasks are going to appear at the top.
TODO: describe the process of setting up the manager user and Member<->Manager approval process.