In larger groups, the leader must devote more effort to leading than to participating in the task execution per se.
This is necessary because the “amount of leadership” required for the successful completion of large-group tasks is greater than that required for the succesful completion of small-group tasks.
This is viable because larger groups can more easily “pick up the slack” from a leader who must devote much of his effort to leading (compared to small groups, where everyone must contribute substantial effort to task execution, else the group fails to achieve its goal).
Nevertheless, when the tasks a large group faces become more challenging, and thus require more of group members in order to ensure success, it becomes increasingly important that the leadership role be taken up by someone whose contribution to the group effort aside from leading it, is least important (relative to the contributions of other group members).
(Delegation of leadership responsibilities can alleviate this somewhat, but ultimately it only delays this effect; at some point in the task difficulty curve, these concerns return in full force despite any amount of delegation—which, in any case, will also be necessary.)
(None of these insights are new, of course—these points have been noted before, in the context of, e.g., startups. It is, in any case, interesting to see them arise in this very different context.)
Addendum I
In larger groups, the leader must devote more effort to leading than to participating in the task execution per se.
This is necessary because the “amount of leadership” required for the successful completion of large-group tasks is greater than that required for the succesful completion of small-group tasks.
This is viable because larger groups can more easily “pick up the slack” from a leader who must devote much of his effort to leading (compared to small groups, where everyone must contribute substantial effort to task execution, else the group fails to achieve its goal).
Nevertheless, when the tasks a large group faces become more challenging, and thus require more of group members in order to ensure success, it becomes increasingly important that the leadership role be taken up by someone whose contribution to the group effort aside from leading it, is least important (relative to the contributions of other group members).
(Delegation of leadership responsibilities can alleviate this somewhat, but ultimately it only delays this effect; at some point in the task difficulty curve, these concerns return in full force despite any amount of delegation—which, in any case, will also be necessary.)
(None of these insights are new, of course—these points have been noted before, in the context of, e.g., startups. It is, in any case, interesting to see them arise in this very different context.)