Why is it necessary to appoint a team captain?
A team’s captain is very important for the organisation. That’s because he or she is the contact for the whole team. Among other things this means that all correspondence for the team is addressed to the team captain, and that the team captain has the obligation to inform his team members. It also means that the team captain acts as a mouthpiece for the team towards the organisation. Team members can contact him or her for questions, which he or she may forward to the organisation. The team captain is also the only one who has access to the team portal to manage and change the team details. You can read more about the team portal here.
Note that if your team captain has a role during the Roparun (for example a runner) someone else must be available.