Flowcharts and state diagrams are principally good for:

Flowcharts and state diagrams are primarily effective tools for describing the behavior of systems. They visually represent the various states a system can be in and the transitions between these states based on specific inputs or events. This representation allows for a clearer understanding of how a system operates, making it easier to analyze processes and identify potential issues or areas for improvement.

In the context of engineering and software development, these diagrams help in delineating the logic of algorithms, processes, or systems, which is essential for ensuring that all team members and stakeholders have a consistent understanding of what the system does and how it reacts to different conditions. This visual approach simplifies the complexity of technical systems, facilitating discussion around requirements and design.

While communication among stakeholders is certainly an important aspect of project management, flowcharts and state diagrams serve a more specialized function in illustrating system behavior rather than serving as primary communication tools. Additionally, they do not specifically address the financial aspects of a project or marketing efforts, which involve different types of analysis and representations to evaluate budgetary considerations or promote a product to consumers.