To Complete a 3L5W Analysis Using QI Macros Template Test of root cause logic: Third why happens, therefore, the second why happens, therefore, the first why happens. Example of QI Macros Three-Legged Five Why Template in Excelįive why's of root cause analysis: first why happens because of the second why which happens because of the third why. It also distinguishes between three types of failures using the three legs of: specific problem, detection failure and systemic failure. Why it Matters: The three-legged five why (3L5W) template is similar to a fishbone or Ishikawa diagram. However, the 3L5W template puts additional emphasis on testing the logic of your cause and effects analysis. Lean Six Sigma Templates » Three Legged Five Why Template Need to Perform a Three-Legged Five Why Analysis? QI Macros has a Ready-Made 3-Legged 5 Why Template for Excel! Free Agile Lean Six Sigma Trainer Training.Animated Lean Six Sigma Video Tutorials.Statistical Analysis - Hypothesis Testing.