This is related to system capacity, which is severely tested on Mother's Day, or when degraded due to a natural disaster. Service systems frequently involve people, time, and resources. This is another logical system. Directives may originate in a strategic plan, and may be transmitted through a system, modified as they go depending on the context of the component they are in. Directives typically transit more than one level before they result in work that affects measurable outcomes.
Flows occur due to the logic of how the system components are connected.
Understanding the flows implies understanding this logic. In some systems, knowledge of the flows alone might be sufficient to allow analysis of the system. Things to think about Imagine a simple task which consists of a set of sequential operations. Sketch a simple flow diagram of this task, and call it a system. Now consider a different task of sequential operations.