Using root cause analysis to identify issues

What is root cause analysis?

In business, the symptoms of a problem tend to be addressed rather than the issue itself. Of course, if you only fix the symptoms, the issue won’t go away, and the costs associated with dealing with the symptoms will mount up.

However, if you identify the root cause of the problem, you can fix any underlying issues and eliminate the costs of treating symptoms altogether.

Root cause analysis is a Lean Management technique that helps you answer the questions of why problems are occurring. It aims to identify the primary cause of the issue at hand.

You begin with the symptoms and work backwards to identify the origin of the issue, and then by tackling this root cause, you can prevent it from happening in the future.   

An example is a leaky storage container. If you keep patching up a crack, eventually, the costs associated with losses, replacement tape and labour will amass to the cost of replacing the container in the first place.

Common issues

There are three common types of issues:

1. Physical issues

This is when materialistic items are at fault and is commonly due to depreciation. One such example is a conveyor belt that has stopped operating due to rusty parts.

2. Human issues

This is when people working within the business have mistakenly done something wrong, or that was not required. An example is adding too much oil to the engine of a tractor resulting in engine failure.

3. Organisational issues

This is when a faulty process in an organisation is implemented. An example is a process for cleaning equipment when nobody has been assigned to source the materials required. Another example would be if an employee leaves the organisation and their duties are not reallocated.

When conducting a root cause analysis, it is expected that several physical, human, and organisational issues will arise and that there is more than one root cause behind each issue. Conducting a root cause analysis will help you identify flaws in your system and highlight the wide range of adverse effects a single root cause can manifest into.

Conducting a root cause analysis

Identifying the problem

The first step in a root cause analysis is to identify the issue(s) – as highlighted above, this usually begins with symptoms. A waste walk can be a useful way of identifying the symptoms.

Some symptoms will be obvious while some may be more obscure. For example, the root cause for excessive cobwebs could be an abundance of flies, which in turn could stem from a neglected piece of fruit. Regular waste walks and use of systems such as 5s will prevent symptoms from being missed.

Data collection

Data collection provides evidence of the problem and can help you calculate how long it has been an issue. It also provides a quantitative assessment of the impact of the problem. For example, if you measure the amount of produce lost from a leaky storage container, you can work out the financial repercussions the issue is having on the business.

The situation must be analysed in-depth to make sure no potential root causes are missed.

A thorough investigation could also identify root causes for other problems within the business. It is common for a single root cause to create a range of different issues. This is the basis of the Pareto principle (80:20 rule), which states that for many outcomes, roughly 80% of consequences come from 20% of causes.

For example, a rodent infestation could be the root cause of the leaking storage container as well as some electrical faults, disease outbreaks and loss of seed or grain.   

Drilling down and the five whys

Once you have identified the symptoms and the root cause, you need to establish the sequence of events that has led to it. You must identify as many factors as possible and continuously dig for more. By placing these factors in order, you will establish the entire story of what is causing the issue(s).

One way of doing this is by using the 'five whys' technique. You begin with the issue at hand, then ask why this is occurring. When you have an answer, you ask why this is happening, and you repeat this as many times as needed until you establish the root cause.

Example

Q. Why does the storage container keep leaking?

A. It keeps getting damaged

Q. Why does it keep getting damaged?

A. It is being bitten by rodents

Q. Why is it being bitten by rodents?

A. There is a rodent infestation in the store

Q. Why is there a rodent infestation in the store?

A. The store has not been cleaned in a year

Q. Why hasn’t the store been cleaned in a year?

A. The previous cleaner left and has not been replaced

Keep this process going until the root cause of the problem has been identified. Although it is called the ‘five whys’, it can be completed in any number of questions. However, if you reach seven questions, it is an indication that there is more than one root cause.

Act

Once your root cause(s) has been identified, ask yourself what will prevent them from happening again. Consider who will implement any actions and how easily this can be done. It is also essential to undertake a cost-benefit analysis to make sure any changes are financially viable.

In summary, root cause analysis is a valuable and straightforward process for solving problems. By establishing the narrative of events leading up to problems, you can get a comprehensive view of how a single issue can manifest into several others. By fixing the root cause, you should eliminate the issue and associated wastes (time and money) from treating the symptoms.

How to identify areas for improvement

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