A solo developer or small team taking a 0-to-1 idea to delivery needs to move through requirements, research, design, prototype, development, testing and release, and wants rules and hooks to constrain a coding agent's behavior.
Developers writing their own prompts, maintaining project standard documents, or using a coding agent's default workflow.
Coding agents tend to skip requirements and testing and produce unpredictable output, forcing repeated manual correction; the public material gives no user complaints or rework data.