PMD needs volunteers to commit to participate for the whole project, not just part of it, because we need people to work as a team from start to finish, from becoming oriented to cleaning up. Early on from volunteer feedback, we found that people who arrive late or leave early consistently do not feel as satisfied about the work accomplished because they do not see how the work site looked at the beginning or when it was completed, respectively. Since PMD only asks for single project commitment and not weekly commitment or membership dues, we think it is reasonable to ask folks to commit to participate for a whole PMD project.