We plan to implement a detailed 5-Why Root-cause Analysis for all bugs/defects. We have done the back-ground work and are ready with multiple levels of root-causes. Now, we want to implement in our bug/defect work-flow, how do we proceed? Ideally we are looking for a system where the 1st level RCA will have 5-6 points and each-point will again have 4-5 sub-points and so on.