One of the overlooked but very important roles in the world of Ultimate Frisbee Admin and Volunteers is that of the Vice-Captain.
If you run a League or Tournament, make sure you always insist on having Vice-Captains / Number Two's / Second Bananas / Whatever you call them.
Most obviously, they help your event to run better, particularly in the case of a Captain / Number One / Boss disappearing for a little while - the team has someone else that knows what's going on.
Less obviously, but perhaps more useful in the long term, Vice-Captains are proto-volunteers.
Say for example you're the Director of a League, and you want to stand down. First stop to find a new LD is to talk to your Captains about one of them taking on the role. I mean, they've shown that they're willing to do some organising by sorting their team, people know them, and they probably have a good idea how things work.
Having Vice Captains around obviously expands on your pool of possible recruits, but also helps you when one of the Captains says "No." You can say back to them "Well, if you're saying 'No' because you're worried about who's going to manage your team then you shouldn't, because you've got this great Vice-Captain who can take it on." Or you can say "Well, fair enough to say 'No', but do you know someone who might say 'Yes' (maybe your Vice-Captain?)".
So to conclude - if you're running a league or tournament, insist on there being Vice-Captains as well as Captains - for the good of Ultimate Administration and the long-term renewal of Ultimate organisers.