Personal Story
I've joined organizations (the LA Stage Alliance is one) where I've seen that my combination of vision, expertise, and leadership skills would be a bundle that is lacking - but I've stepped away from others (such as college sports teams and musical ensembles) where I could not add real value.
Self Assessment
8 - I will only take on activities and positions where I can be a genuine help, and not ones where I can add less value than another candidate.