Static analysis is for life, not just for christmas. While finding bugs is before execution a staple, static analysis provide tools to go even further. It scans the code to offer suggestions, training unususpecting developer into using modern PHP code, or simply local patterns. It provides inventories, linking remote parts of the code by their value and process, and bringing more consistency across the whole code base. Finally, it can document the code base, and keep it real-time. The best is that each of those mission has available tools for the job.