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Identifying root causes: a review of two tools

1 November 2017
Nurit Lin

Nearly every debriefing process, certainly those conducted according to the two leading lesson learning methodologies (namely: AAR and Classic Debriefing), lead to a moment in which we are required to identify what caused the revealed gaps and what root-cause lays behind these causes. This stage is the most a central, vital and rewarding stage of the debriefing process. This is the stage in which, following an arduous analysis of "what happened" (i.e. a sequential recap of events) and "what we expected to happen" (i.e. what is procedure in this situation) we finally arrive to a certain clarity in which everything clicks together. This comprehension is quite elating; the realization we unraveled the root problems which if solved can in turn alleviate our other obstacles. We can now make meaningful decisions.

So, how is this done? How do we move on from merely recognizing the gap between ideal and real and begin understanding their root causes? How do we ensure that we don’t remain content with unearthing the initial and superficial layer (i.e. symptoms) and drill our way to the foundation from which our problems stemmed?

Two central tools may prove useful for this task: the 5why's and a present tree:

A. A present tree is a graph of all problems we’ve identified during the review process which assists us in identifying the logical link between cause and effect, searches for the factor that led to each cause thus revealing which elements are symptoms derived from other factors and which are actually root causes. This method is referred to as a present tree since it charts the organization's current condition in terms of the review's subject. This is performed in four stages:

a. First, write down all causes identified. In event of a failure, we will use negative terms. When dealing with success, use proper terms. Each event is then numbered.

b. We then search for factors linked as cause and effect and make note of this logical connection by writing "A leads to B".

c. Pair as many factors as causes and effects as possible till you contract the tree to a single cause unaffected by another cause. This is, by definition, the root cause.

d. Now that the root cause has been pinpointed, we can suggest a solution to this initial problem. These are the lessons and insights we must transform into executive tasks so that they do not remain purely theoretical. Some perform this process by using a future tree which involved charting several possible solutions and suggesting solutions for the problems these suggested changes might generate.

B. 5why's: if you find charting a graph complex and intimidating, the 5why's methodology is the exact opposite as it is simple and easy. Developed by Taichi Ono, the mind behind Toyota's manufacturing method, it is so simple that anyone who at any time in life was a parent to an infant is familiar with the phenomenon: asking why, why and yet again why. Indeed, this method's basic principle is to ask 'why' five times regarding any identified gap in order to reach the root cause. Obviously, the amount of numbers isn't etched in stone. Some debriefs require only 3 'why's, others 8. When do we know to stop? First, when we reach an element which affects the process and is neither a fact nor a symptom. Second, when we reach elements beyond our sphere of influence.

How do we know which tool is preferable in which situation? Is the 5why's method apt for simple situations due to its simplicity and the present tree appropriate for more complex scenarios? The answer is no, just as we don't prefer classic debriefing over AAR when facing a complex case (despite it indeed being a more complex methodology). These are different tools and methodologies that can be utilized by organizations according to their culture and preference. Both debriefing processes and root cause identification tools are adapted, customized and merged in order to fit the organization's needs and conditions.

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