© 2016 Dwellworks, LLC
Page 10
Lean & Agile Playbook v.2.01 – modified MAY2016
The Tools
The 5 Whys
An iterative, interrogative technique used to explore the cause-and-effect relationships
underlying a particular problem. The 5 Whys is a simple, practical tool that is very easy to
use. When a problem arises, simply keep asking the question "why" until you reach the
root cause of the problem, and until a robust counter-measure becomes apparent. The 5
Whys is most effective when the answers come from people who have hands-on
experience of the process being examined. The "5" in the name derives from an empirical
observation on the number of iterations typically required to resolve the problem.
How to complete the 5 Whys:
+ Write down the specific problem. Writing the issue helps you formalize the problem
and describe it completely. It also helps a team focus on the same problem.
+ Ask Why the problem happens and write the answer down below the problem.
+ If the answer you just provided doesn’t identify the root cause of the problem that
you wrote down in Step 1, ask Why again and write that answer down.
+
Loop back to step 3 until the team is in agreement that the problem’s root cause is
identified. Again, this may take fewer or more times than 5 Whys.