Problem Solving

The 5 Whys

Description

This technique establishes the root cause of a problem by repeatedly asking the question "why" (five is a good rule). It is a useful technique for identifying improvements and implementing lean thinking.

When should it be used?

It should be used when the root cause of a problem needs to be identified.

What will you get?

You will identify the root cause of a problem. It will allow you to determine the relationship between the root cause and the resulting effects. This will assist you in identifying the most appropriate solution to a problem and the benefits the solution will bring and how that cause can be removed to improve the process.

The process

Identify the problem and ask the question 'why' until you establish the root cause - for example:

Problem - the aeroplane crashed

Why did the aeroplane crash?

. because the pilot ejected

Why did the pilot eject?

. because the wing fell off

Why did the wing fall off?

. because of a stress fracture

Why was there a stress fracture?

. because our maintenance procedures were not applied

Why were our maintenance procedures not applied?

. because our maintenance procedures were not known to the servicing depot

Root Cause Analysis

Description

Root cause analysis is a structured technique focused on finding the real (root) cause of a problem, to enable it to be dealt with at source rather than dealing with its symptoms.

When should it be used?

It should be used when the true reason or existence of a problem needs to be identified.

What will you get?

You will get a logical representation of a problem, broken down into its elements. This will provide an understanding of:

. What has happened.
. Why it happened.
. What can be done to prevent it happening again.

Pareto analysis

Description

The Pareto principle also often referred to as the 80:20 rule, suggests that a vital few factors are responsible for most results i.e. the majority of results (80%) have very few causes (20%). It enables you to identify and focus on those areas where there will be the greatest effect.

When should it be used?

It should be used to help identify the issues to focus upon based on the assumption that these will be the greatest return for effort.

What will you get?

You will get a list of areas/issues to enable you to decide which to work upon for the greatest benefit within your project.

The process

. Identify the scope of what you wish to analyse.
. Establish what data is available and gain access to it.
. Sort the data based upon the factor in which you are interested (in the following example this is inventory value).
. Normally the top 20% (approx) will contribute to 80% (approx) of the cause e.g. 20% of items will contribute to 80% of the inventory value.

An example is simply demonstrated below in the following inventory:

. 1 item (20% of items) contributes to £32m (80% of the total inventory).
. When deciding where best to focus effort Pareto analysis points you to item 'a' as any change will have greater effect.