For so long I have desired to be a part of different groups, sometimes I was accepted, other times I had to start my own. I think its a basic need of most people to feel included. They want to find somewhere they belong, where they are accepted.
Churchs are infamous for having groups. Usually, they have the group who does all the work and the group of people who only show up on Sunday. The leading group is usually very cliquish, just like highschool. Anyone new who joins has a hard time breaking into that. I once heard that 10% of the people do 90% of the work in a church. I believe it, but the part of that stat I have a problem with is the 10% doesn't give the 90% an opportunity to contribute.
Opportunity is key. If a need arises and the 10% just solve it without giving others a chance to help, they are hurting the 90%. Not everyone always jumps up and says "Me first!" Think back to elemenatary school, there was always that kid who raised their hand with the answer, but often times the teacher would call on someone else. The second kid may have something great to contribute, but is reluctant or thinks they don't matter. A good leader will see the potential in the non-pushy people and give them an opportunity to shine.
The point of all this? People need to be INCLUDED. Don't exclude people, because someone else volunteered first. Don't leave people out and make them think they don't matter. Good leaders know how to step back and give everyone an opportunity to become an important part of the group.
Update: You can read Stew's comments on this post at his blog.