Size of groups and role of members

As soon as a group is over a dozen people, each member adopts a proactive, observer or idle position and can move from one to another according to a number of criteria. Rather counterintuitively, it is observed that the percentage of active persons stays remarkably constant (principle of 90-9-1): proactive people are one and over percent and reactive peoiple are between ten and a few dozens of percent.

Different types of groups differing from the number of members:
Small groups up to twelve people whom can be managed restrictively (expecting the action particular to each different member);
Intermediates groups between twelve and a hundred people whom need more efforts from the manager to get reactions;
Large groups between a hundred and one or two thousand people which allows to produce collaboratively... provided a focus is done on reactive persons;
Very large intermediate groups of several thousand people where the group composed by proactive people becomes easily illogical;
Very large groups over several dozens of thousand where proactive people are numerous enough to make management less restrictive.