Every event is result of causal chain, in that something has happened because on something else has occurred. Its often important to understand why something has happened in order to mitigate the negative effects and prevent it from happening again.
Root cause analysis (RCA) is the process of discovering the root cause of the problem in order to identify the appropriate solution.
Cause and effect diagram, most commonly know as fishbone diagram is the simplistic and effective way of identifying the root cause of the defects. The diagram is also referred as Ishikawa diagram, Herringbone diagram or Fishikawa (Fish diagram created by Kaoru Ishikawa)
In this diagram, the head of the Fish on the right is represented by the resulting event which usually is a defect, problem or a challenge and the causes on the left in the form of the fishbones. Each bone represented a major group of causes and sub-branches are root causes.
Main branches of bones are categories depending on the type of the problem for be RCA. Brainstorming techniques like why-why analysis, how-how analysis (to keep getting to the root causes) are commonly used.
Categories are usually grouped as below but cane be changed as needed
Ms - Man, Machine, Material, Methods, Measurements, Medium, Mission, Management, Money, Maintenance, Mother Nature, Mind bias etc
Ps - People, Product, Process, Price, Place, Position, Performance, Proof, Promotion
Ss - Surroundings, Suppliers, Systems, Skills, Safety
