Product management is involved with most internal groups, but not equally and not all at the same time. PMs need to exert enough gravitational pull to keep each organization in its correct orbit, and still save some energy for customers. So let’s give our planetary analogy a spin. Starting with Engineering… In the traditional waterfall model, a typical project is scheduled for 9 months, but inevitably takes a year to complete. So we’ll assign classic software development groups to Earth in our product solar system, with a 365 day cycle.