Failure is a part of doing business. However, the sooner you can identify and correct the root cause of a failure, the smaller its impact is. A systematic approach to pinpointing the root cause of a failure is beneficial in any job function and industry. Root cause analysis methods, including the eight common tactics below, minimize the impact of failed processes or systems.
1. Five Whys
The Five Whys method asks why a problem is occurring five (or more) times. The answer to the first question shapes the second question, the answer to which shapes the third question, and so on. This method works well for less complex concerns and can also serve as a starting point for thoroughly describing more complicated problems.
For when: A team has limited root cause analysis experience.
2. Challenger Interview
Often, shareholders have general concerns which they articulate as a specific problem. However, using the Challenger Interview method to further understand the concern actually uncovers an underlying issue different from the problem originally communicated. This methodology, similar to the Five Whys method, identifies the core issue by asking, “Why?”
For when: The problem must be identified before the root cause can be.
An oft-used tool in many facets of business, the flowchart also has a place in root cause analysis. When multiple people contribute to mapping the failed process or system, it may be easier to identify breakdowns and, therefore, a root cause.
For when: Visualizing the process could illuminate the root cause.
4. Change Analysis
If a failure occurred after a recent update, the preferred root cause analysis method is likely Change Analysis. This tactic compares data, procedures, and inputs from before and after the failure to single out a root cause brought on by the change.
For when: A recent change could be the root cause.
5. Fishbone Diagram
Also known as a Cause and Effect or Ishikawa diagram, a Fishbone Diagram guides brainstorming sessions about potential root causes. The diagram groups potential root causes by category to make investigating these inputs and determining solutions easier.
For when: A large number of concerns could be the root cause.
6. Scatter Plot
After determining potential root causes with a method such as the Fishbone Diagram, you may be able to identify causation, and therefore determine a root cause, with a Scatter Plot. Comparing two variables, which in this case are a suspected cause and known effect, allows you to see whether or not one is caused by the other.
For when: Correlation between potential causes and known effects needs to be determined.
7. Pareto Diagram
The Pareto Principle states that “80% of consequences come from 20% of the causes.” A Pareto Diagram is a bar chart that identifies the most frequent root causes of identified failures. This visualization allows teams to prioritize the small number of causes that lead to the majority of problems.
For when: Root causes need to be prioritized.
8. Failure Mode and Effects Analysis
The Failure Mode and Effects Analysis (FMEA) identifies individual failures and examines the impact of those failures. The multi-step process is a complex root cause analysis method that is best used in technical environments.
For when: A new product or process is being developed.
Benefits of Root Cause Analysis
The systematic approach to problem solving offered by root cause analysis offers benefits to a wide range of job functions and industries. Most importantly, these strategies allow you to identify and correct the root cause of a problem, rather than treating symptoms caused by the primary issue. Using a defined methodology clarifies the situation and encourages you to look for faults in processes, rather than people. When root causes are addressed (especially early), organizations see increased output and improved quality.