This technique was pioneered by Kaoru Ishikawa, a Japanese professor and quality management expert. An Ishikawa Diagram visualizes a problem and explores the cause and effect relationship by categorizing potential causes in order to identify multiple root causes. Importantly, as shown in Figure 12, Ishikawa identifies the factors which have a high or low impact on the problem so that multiple root causes can be prioritised.
Figure 12: A Route Cause Analysis Fishbone (Ishikawa) Diagram