Robert Michels discussed extensively the impact of party size on the quality of participation of members within a political party. "As parties grow in size and complexity, the relationship between the top and bottom of the hierarchy also becomes more complex". For Michels the advance of organization and consequent decline of democracy seems to be an inevitable process even for an organization formed with democratic aspirations. A complete theory of party organizations should account and control for the impact of the environment since the environment obviously affects the shape and behavior of the organization. Whether a country is geographically large or small is often said to affect distribution of power between a political party's national organ and the local organs. One other system-level factor that is said to affect the complexity of the party organization is the population size of the country.