Six Sigma Tools you can use for the DEFINE Phase

Six Sigma is a disciplined approach and it follows the DMAIC methodology. We call it structured because you have to work in an orderly fashion of Define – Measure – Analyze – Improve and Control. Each stage has a set of Six Sigma tools (though some tools can be used interchangeably). In this blog, I want to talk specifically about the tools used in the Define Phase.

Recommended Read: 08 great online resources for learning Lean Six Sigma

What is expected in the Define Phase ?

Stating simply, in define phase, the problem is defined!

Hold on, it might sound simple , but actually it may not be ! Let’s see why .

Funneling tools for Six Sigma Project Selection

When you are assigned with a Lean Six Sigma project, you may be given tasks like reduce rejection ppm , improve OEE , increase customer satisfaction. This is what the organization’s management desires. Unfortunately, this can’t be take up as a Six Sigma project, because that’s too wide a scope. It needs to be drilled down. The tools that we used to drill down are : Why-Why Analysis , 5W  2H or Pareto Analysis.

These tools help in drilling down the issue and reaching to tech y. The management desires are denoted as Big Y and the process outcome , that you want to improve are known as tech y.

Let’s take an example to understand this . Let’s assume that XYZ company makes self adhesive labels and the rejection %age is going higher that the expectation. The management wants a Green Belt resource to take up the project of reducing the rejection %age. Let’s say Jatin is the Green Belt resource who is employed to work on this project. 

 The first thing that Jatin needs to do is to drill down to identify his tech y. For this he first of all identifies since when the rejection % has started increasing the benchmark. He finds that the phenomenon started happening since last 6 months. Then he creates a Pareto of rejection contribution vs the product type.

Pareto clearly shows that there are focus items – product 1 & product 2. Thus he narrowed down his project from improving organization’s rejection ppm to improving rejection % of product 1 & product 2. He has now 2 Six Sigma projects as the two products should be treated separately. 

The other question is how much improvement should he be targeting ? For this he can use bench-marking. Bench-mark a similar product / process.

The other way to define a problem is 5 W 2 H. Let’s understand 5W 2H first.

5W – 2H

5W -2H consists of –

WHAT –  What implies what is the reported problem. Most of times , the person who is complaining may not be able to technically tell you the real issue, but it’s important to note down what exactly is he or she experiencing .

WHO – Who is experiencing the problem ? Many a times, the person who reports is different that who complains. For example, Quality representative may raise a supplier complaint , but it is the operator at line who would be experiencing the problem.

WHEN – When did the issue occur during the product life cycle. The product life cycle has typically three stages – Infant , Useful life and decline . Getting to know at which stage did the issue occur helps to tackle the issue in a better way.

WHERE – Where did the problem occur?

This could mean a geographical Location like East, West, north or South. Or it could mean in which component or sub-component did the issue occur.

WHY  – why the customer thinks it’s a problem. Against which standard is he or she complaining ?

How – How did the problem occur? Implies the mechanism or science of failure

How – How many problems occurred?

This implies Complaint counts, Rejection rate % etc.

Let’s take an example here. Jatin is asked to reduce the number of customer complaints that have suddenly increased in last quarter.

Again Jatin is handed over this problem and he is asked to take up a Six Sigma Project on it.

This is how he drills the issue using 5W2H:

20 complaints of scratch lines received in the month of April’17. (The product was launched in March’17, so it’s in Infant stage of Product Life Cycle).The customer observed the issue as soon as the material was opened. The problem has been observed in PE Laminate from the material produced in week 1 of March’17 and shipped in Southern region from all the customers. A total of 10 K sq.m of laminate is under complaint . The mechanism of failure could be the new packing material employed for South region.

Now, the Six Sigma Project will be to reduce the customer complaints in the Southern region for PE laminate. Of course, more work needs to be done  to write the exact Problem Statement and Project objective, but first step of drilling down has been done.

Project Scoping Tools :

Once first level of drill down is done, identify the x’s (the independent variables that affect the tech y). Then create a SIPOC. SIPOC stands for Supplier, Input, Process, Output and Customer. This tool is a gap assessment tool and it also scopes your project . You define boundary of your project employing SIPOC and helps avoid scope-creep.


Some people also prepare a high level process map before making a SIPOC. Some professionals prefer making a process flow diagram rather than making a SIPOC.

Project Initiation Tool

After identifying the project , a project charter is prepared. Here is a sample Project Charter.

Project Charter

Summarizing, here what is required in the DEFINE phase

Objectives of Define phase :

  • Identify the Big Y (Top Management demand or feeling)
  • Identify tech y ( Technical y, drilled down to a process)
  • Identify probable x’s and form the equation y = f(x1,x2,x3…)
  • Create a SIPOC
  • Create a Project Charter
  • Calculate COPQ (Cost of Poor Quality) to form basis of ROI
  • Calculate ROI

Here are the tools that enable you complete you DEFINE phase :

Tools used in the Lean Six Sigma Define Phase

  • Tools to drill down tech y – Why-Why, Pareto, 5W2H
  • Tool to define scope – SIPOC, High Level Process Map, Process Flow Diagram
  • Tool to summarize Project – Project Charter

Want to know recommendations of experts on Six Sigma tools ? Here it is :

Listen from the experts – What tools do you think are a must for an effective Six Sigma project?

Leave a Reply

Your email address will not be published. Required fields are marked *

Sign up to our newsletter!