For developers

Clear requirements: Understanding what needs to be done, not why, before writing code
Ready plan: Technical design with architecture, data, and error handling
Less stress: Issues are identified at the planning stage, not in production

For managers/team leads

Accurate estimates: Realistic timelines and efficient resource allocation
Transparency: Complete picture of task complexity and team progress
Risk management: Technical issues are identified before work begins

For customers/product managers

Result guarantee: Exactly what the business needs will be built
Clear communication: Specifications as a common language for discussing functionality
AI-ready: Specifications and guidelines - perfect context for AI agents