This statement implies that an organization cannot simply be made up of a random group of people. If that is so, then we must ask what does make an organization. The first inference I draw from this statement, then, is that an organization must have a purpose. The organization must exist to serve some purpose that is important to its members.
A second thing that can be inferred from this statement is that an organzation does not need to be limited to a particular physical place. An organization can be any group of people who are associated with one another for a given purpose. In other words, having a common purpose is much more important than being in a common place.
So this statement implies that organizations must have purposes and that they need not be made up of people who are in the same physical place.
A group does not constitute an organization. That group must be organized which requires forethought if that group is an organization. In other words, for a group to be an organization, it must have some reason for organizing as that group; perhaps they have similar beliefs or they rely on each other in some interdependent way such as in a family or a business. Think of the word “organ”-ization. Your organs all work together to keep you alive. They are grouped together because of this interdependency. Analogously, people work together in an organization and the way the organization is structured (or the way your body is constructed) depends upon how the component elements work together or how/why/where they gather together. The structure of an organization (in your example as a group of people) is determined by its network of processes, which is a way of saying the structure of an organization is determined by the organizing itself. How and why and where the component elements organize will determine how and why and where they organize; as a group of people, organs, or a network of bloggers. To be an organization, the ‘group’ must have some kind of unified purpose.