Why Why Analysis Training Material

3x5 Why-why Analysis

- A new approach for root cause analysis

1st _{Supplier Quality Day * 27NOV09}

3x5 Why Why Analysis Content

A.

The 3x5 Why Project Background

B.

The 3x5 Why Method

C.

The 3 x 5Why Focus

D.

Templates

ST target is to share with our suppliers a common approach

for problem solving methods especially for “3x5 Why why “

tool , to get complete, exhaustive FA report and to avoid any

recurrence.

Naze-Naze / 3x5Why-Analysis

Project Background

A. The Naze-Naze Project

Background

The Situation

1.The Need of our Customers

* To understand each 8D-Report from semiconductor and passive suppliers in depth

* To understand if the problems are solved in a way that they never reoccur

Remark: Having reached ppm-level, our customer fails enable ST and their customers /

suppliers to look at each 8D-Report in depth.

2. Improvement of 8D-Quality by Why-Why-RCA (Root Cause Analysis)

In 2009, ST takes the next step and has started a project with our key suppliers. Focus on:

฀* Implementing Why-Why-Analysis for non-conformance and non-detection aspects

including system root causes

฀ * Getting a common understanding of a sustainable problem solving process

฀ * Having a comprehensive documentation of each failure which is understandable

on a general technical knowledge level for our customers & management.

฀ Hint: This project is part of the 8D improvement initiative which is measured acc. Toyota

寻根究底 寻根究底 寻根究底 寻根究底

Naze-Naze / 3x5Why-Analysis

Project Background

Motivation

ST is the Top 3 automotive electronics supplier.

All automotive customer request is “ZERO FAILURE” However, ST devices didn’t reach the target :

• some failure were reoccurrences, special caused by quality excursions material.

• quality level is improving very slowly.

⇒there is a strong need for persistent improvement

• requires systematic application of lessons learned

• prerequisite: full understanding of real root causes (technical and non-technical)

=> method: 5 why analysis (naze naze), from Toyota

Naze-Naze / 3x5Why-Analysis

Project Background

Role of Naze-Naze Champions

Internal and Supplier’s 5Why-Champion

Name: - Reviewed and Agreed by STM management

Task: - Leading of internal 5Why project, roll-out to all divisions and plants, Develop to all key suppliers.

- Encourage and support 8D-Engineers in applying the 5Why problem solving method

- Assure that technical & systemic root cause is analyzed and eliminated for “prevent” and “escape” aspect=> avoidance of recurrence.

- To be trained and evaluated by ST QA.

- Involving management team into Naze-Naze Method.

Naze-Naze / 3x5Why-Analysis

Project Background

Naze-Naze / 5Why-Analysis Method

Historical Background

Although the 5-Why problem solving technique has been popularized by the Japanese, this common-sense concept has been around for quite some time.

•฀ For want of a nail a shoe (hoof) was lost,

•฀ for want of a shoe a horse was lost, •฀ for want of a horse a rider was lost, •฀ for want of a rider an army was lost, •฀ for want of an army a battle was lost, •฀ for want of a battle the war was lost,

•฀ for want of the war the kingdom was lost, •฀ and all for the want of a little horseshoe nail.

John Gower‘s <Confessio Amantis> dated approximately 1390 AD.

Naze-Naze / 5Why-Analysis Method

Historical Background (cont.)

One of Ohno´s habits was to repeat asking 1. why the problem happened

2. why the problem was not prevented ฀ -why–why-why-why…..

until the real root cause was found.

This habit has been preached to overseas

transplants of Toyota.

All Toyota employees are trained through

their daily jobs to find out problems, root

causes, countermeasures in this way. His habit became a Toyota´s culture.

This culture is one of the keys of Toyota´´´´s

success today, that is realized by enthusiastic

problem finding skill of every employee.

Having no problems is the biggest problem of all

Mr.KAIZEN Mr.KAIZEN Mr.KAIZEN

Mr.KAIZEN „„„„TaiichiTaiichiTaiichiTaiichi OhnoOhnoOhno“Ohno“ (1912““(1912(1912(1912----1990)1990)1990)1990) Former executive vice president of Toyota who established Toyota-Production-System, which is known by “Kanban”. His philosophy is still alive in today's Toyota way.

"Ask ‘why’ five times about every matter."

1. "Why did the robot stop?"

The circuit has overloaded, causing a fuse to blow. 2. "Why is the circuit overloaded?"

There was insufficient lubrication on the bearings, so they locked up. 3. "Why was there insufficient lubrication on the bearings?" The oil pump on the robot is not circulating sufficient oil.

4. "Why is the pump not circulating sufficient oil?" The pump intake is clogged with metal shavings.

5. "Why is the intake clogged with metal shavings?" Because there is no filter on the pump.

Link to the information source:

http://www.asahi.com/jinmyakuki/TKY200509290213.html http://www.toyota.co.jp/en/vision/traditions/mar_apr_06.html

Naze-Naze /5Why-Analysis Method

Purpose of Naze Naze Analysis (5 x Why)

•

Question:

How are you sure that your Naze-Naze Analysis is

performed properly?

•

Answer:

When real root causes are identified,

there should be

no reoccurrence

of failures!

•

The purpose of Naze-Naze Analysis:

To

prevent reoccurrence

of failures by implementing

correct countermeasures on real root causes

Naze-Naze / 5Why-Analysis Method

What does “Problem” mean?

“Problem” is defined as

a gap between

“the way it should be”

and “the way it is”.

Naze-Naze / 5Why-Analysis Method

Problem description

First step of problem solving!

If a problem is described wrongly,

the result of problem solving will be also wrong.

Example of wrong description This is not a joke!

Real example from a workshop with engineering colleagues

Customer give us feedback very late when a delivered sample was out of spec., and we can not make improvement timely.

An out-of-spec. sample was produced and delivered to customer.

Think from customer’s view

Naze-Naze / 5Why-Analysis Method

Basics of Naze-Naze Analysis

Grasp the situation Pursue root causes

Implement effective C/M

C/M to prevent a reoccurrence

Why to do

No reoccurrence should happen when the real root cause is fixed

Analyze with GENCHI-GENBUTSU

1. Organize & narrow down the problem

A complex problem _{ plural individual problems} 2. Localize the problem

Perform GENCHI-GENBUTSU 3. Evaluate the situation of occurrence

Grasp the pattern

1. Shift from “reactive firefighting” to “preventive countermeasure” Firefighting will result in reoccurrence

2. Master the key points of Naze-Naze to pursue real root causes Grasp every factor of the failure regularly, orderly

Naze-Naze / 5Why-Analysis Method

Grasp the situation accurately

Shortcut to real root causes!

3 elements to grasp the situation

① Organize and narrow down the problem ② Localize the problem

③ Evaluate the situation, how the problem

happened

Preparation for

5 x Why

Initial Problem Perception (large, vague or unclear)

Clarify the problem Locate the Point

of cause

Locate the Point of cause to clarify  what  when  where  who  how in GENCHI GENBUTSU

Naze-Naze / 5Why-Analysis Method

Initial Problem Perception (large, vague or unclear)

Clarify the problem Locate the Point

of cause Point of cause Basic Cause/Effect Investigation Direct Cause 5 Why investigation

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2

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5

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G R A S P T H E S I T U A T I O N C A U S E I N V E S T I G A T IO N Source: TMUK PPS

把

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情

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原

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调

查

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Naze-Naze / 5Why-Analysis Method

Grasp the situation accurately ・・・

・・・

・・・

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1. Organize and narrow down

the problem

Often a detected failure is a combination of complex problems

Naze-Naze / 5Why-Analysis Method

Grasp the situation accurately ・・・

・・・

・・・

・・・

2. Localize

the problem

Go back the processes from where the problem was detected

Naze-Naze / 5Why-Analysis Method

Grasp the situation accurately ・・・

・・・

・・・

・・・

Localize the problem

in the history

If different direct causes were set in different timing or many persons were involved, list up all the events chronologically with evidences.

Evaluate each action if it was correct or not. Email, letter, documents, etc…

Exa

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His

tory

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art

Example

Naze-Naze / 5Why-Analysis Method

Grasp the situation accurately ・・・

・・・

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Naze-Naze / 5Why-Analysis Method

Fact analysis ・・・

・・・

・・・

・・・find important factors

• Compare no problem time and problem time

• If not yet clarified, use Ishikawa diagram

• Always consider with 5M1E

5M1E

Man Machine Material

Method Measurement

Environment

Naze-Naze / 5Why-Analysis Method

For your successful Naze-Naze analysis

Understand the function and construction of the object well

• Product: understand the function and construction with parts, drawings, etc…

• Management: confirm the process and function with working process flow, rules, documents, etc…

• Search in two dimensions of “Produced” and “Delivered”

Naze-Naze / 5Why-Analysis Method

Drill for important factors deeper with

Naze-Naze analysis

Do not jump immediately to investigate countermeasures. Do Naze-Naze analysis to search real root causes.

Repeat asking “why” at least 5 times.

However this does not mean to repeat asking

meaninglessly “why” just 5 times,

but to find the real root causes.

Direct Cause 5 Why Investigation

Root Cause

Naze-Naze / 5Why-Analysis Method

Difference between “containment” and “preventive” measures

Naze-Naze / 5Why-Analysis Method

Difference between “Technical” and “System” root cause

Naze-Naze / 5Why-Analysis Method

Example entered into excel-template

Naze-Naze / 5Why-Analysis Method

How Yokoten works in Toyota *Depending on the severity, escalation level is decided.

C/M should be implemented not only in technical aspect, but also system aspect**.

水平扩展 水平扩展水平扩展

水平扩展、、、、水平展开水平展开水平展开水平展开

Naze-Naze / 5Why-Analysis Method

Key Points：

：

：

：

① Define “1st Why” from principle

② Describe only things differing from normal state

③ Verify the hypothesis as soon as a hypothesis is made ④ Do not diffuse the problem (avoid subjective issues)

⑤ Avoid searching for causes under psychological (心理上的心理上的心理上的)aspects心理上的 ⑥ Describe simply (not two facts in one sentence)

⑦ Avoid ambiguity (含糊不清的unclear expression like “bad” or “insufficient”) ⑧ Clarify the comparative object when an adjective is used

⑨ Repeat “why” until a cause which can lead to a preventive countermeasure is found to avoid a reoccurrence

Naze-Naze / 5Why-Analysis Method

① Define “1st Why” from principle

Focus on the problem phenomenon and define “1st Why” upon the principle of the problem

Problem 1st _{Why 2}nd _Why

Naze-Naze / 5Why-Analysis Method

Thoroughly Pre-Investigation first

These 2 causes are to be found

through thoroughly pre－－－－

investigation. They are not necessarily part

Naze-Naze / 5Why-Analysis Method

② Describe only things differing from normal state

< Bad example > Dust level increased in clean room Machines create dust Machines are operated with full capacity Production volume is big Demand increased

Naze-Naze / 5Why-Analysis Method

③ Verify the hypothesis as soon as a hypothesis is made

• Verify the hypothesis immediately if possible, even during

Naze-Naze analysis.

• Verify by facts based on: SANGEN-SHUGI (Genba 现场现场现场现场,

Genbutsu 现物现物现物, Genjitsu 现实现物 现实现实现实), interview, reproduction test, etc…

Principle of the three “Gen”s – real place, real thing and reality.

Two methodologies:

my eyes and my legs.

Naze-Naze / 5Why-Analysis Method

④ Do not diffuse the problem

⑤ Avoid searching for causes under psychological aspects

It is difficult to make effective countermeasures against mental

aspects to prevent reoccurrence

< Bad example > < Bad example > Motor overheate d Insufficient lubricant Lubricant forgotten Insufficient maintenance managemen t Manager does not know GENBA Wrong manager at the post Mr.A got his head injured

Mr.A hit his head at the edge of the ceiling Mr.A did not pay attention Mr.A was careless Be careful when walking

Why Why Why C/M

The story was diffused due to missing description of what “insufficient” is Avoid subjective issues, i.e. ＜Bad example＞ personal skills

Naze-Naze / 5Why-Analysis Method

⑥ Describe simply

Describe simply with subject + verb

Do not describe two facts in one sentence

（risk to miss other causes)

+ when, where, how, etc…

Only 1 subject in one

sentence

Be careful with „and, or, therefore, because, thus“

< Bad example >

The battery has not been replaced for long time and the pointer cannot be turned on.

Separate into 2 sentences

The battery has not been replaced for long time The pointer cannot be turned on

The battery has run down

The battery has run down

The spring lost contact with the bulb

More potential causes are successfully found!

Problem

Problem

The pointer cannot be turned on

Naze-Naze / 5Why-Analysis Method

⑦ Avoid ambiguity

Describe concretely

Examples of inappropriate texts (to be avoided)

XX is bad XX is insufficient XX shortage XX not thoroughly done

Operator not enough experienced

Operator did not remember the changeover procedure Operator did not know where the stop switch located

Inexperienced operator was disposed at this process

⑧ Clarify the comparative object when an adjective is used

XX is too big for YY XX is bigger than YY XX is longer than YY The bolt diameter is big

Bolt diameter is too big for the hole diameter The hole diameter is too small for the bolt diameter

Describe

concretely

X

Naze-Naze / 5Why-Analysis Method

⑨ Repeat “why” until a cause which can lead to a preventive

countermeasure is found to avoid reoccurrence

A containment measure cannot prevent a reoccurrence. （See Page 4）Considering the daily operation, stop “why” when a preventive measure which we can maintain is found.

Naze-Naze / 5Why-Analysis Method

Practical hints for your problem solving workshop*

Team member selections:

• Expert team + the persons who were directly involved in the problem. This is not to punish the individual faults, but is to perform “grasp the

situation” with facts. • Manager

Question technique:

• During “grasp the situation”, avoid questioning based on assumptions and concentrate on gathering facts. Otherwise this might guide the team into a wrong direction.

Manager’s attitude:

• Think about why the problem was not predicted nor discovered by manager. Is there anything to improve?

Naze-Naze / 5Why-Analysis Method

Last but not least:

It is necessary to keep on learning in your daily

work in order to improve your Naze-Naze skills.

Is it a reoccurrence?

「Product B was mixed in product A」

After a measure was implemented

Naze-Naze / 5Why-Analysis Method

Practical hints for successful Yokoten*

For a successful Yokoten, the key point is in

“receiver side”.

If the product or process is different, it is easy to excuse

“not applicable“.

Instead of saying “not applicable” quickly, think how the

Yokoten case can be interpreted to your own processes.

Every case is an opportunity of On the Job Training.

Naze-Naze / 5Why-Analysis Method

Before you sign on a problem solving report:

• Is 5 x Why logically done till system aspect?

• Are you convinced that the problem will not happen again?

• Is the report easy-to-understand from customer’s view?

Can you present it to your customer?

Go back with “therefore”

Mindset of coach

The reason that students (my colleagues) are not learning is

because the teacher (I) is not teaching.

Naze-Naze / 3x5Why-Analysis Focus

What is the 3x5Why-Root Cause Analysis?
General:

• The 5-Why Root Cause Analysis technique is a practical and proven tool for elimination of root causes.

• Failing to address the deeply rooted seed of the problem means it will likely recur.

The Method:

• The problem-solver simply asks a Why-question approximately five times in series to analyze a certain aspect.

• Through the 3x5Why-method the root cause can be discovered…

1. in the Manufacturing process to PREVENT failures (non-conformance)

2. in the Quality test inspection process, in order to PROTECT the customer from test escapes (non-detection), and

3. to identify/PREDICT weaknesses in the (Quality) Management or System, in order to exclude recurrence (-> learning organization towards zero defect).

Because

Why

Naze-Naze / 3x5Why-Analysis Focus

Avoid this Pattern

Naze-Naze / 3x5Why-Analysis Focus

Basic Solution Pattern

Naze-Naze / 3x5Why-Analysis Focus

Identification of System-Rootcause

Purpose of 5Why-Analysis:

Identification of the individual

(1) Technical and

(2) System Root Cause

Drill Deep

Definition System Root Cause:

 Organizational causes, that lead to a deviation.

Example: Missing work flows, unclear descriptions and/or responsibilities not defined

 Solution or definition of measures is up to the management System Root Cause

Recommendation:

 In the Fishbone-branch for „methods“ organizational weaknesses can be considered.

Naze-Naze / 3x5Why-Analysis Focus

Summary Why-Why Analysis

Naze-Naze / 3x5Why-Analysis Template

Naze-Naze / 5Why-Basic Word-Template

Corrective Action with Responsibility Date

1 x 5Why : A DD.MM.YYYY

NON-Define Problem CONFORMANCE

(PREVENT) ASPECT: 2 x 5Why: B DD.MM.YYYY Use this path for

the specific nonconformance C1 DD.MM.YYYY being investigated 3 x 5Why : C2 DD.MM.YYYY WHY? NON-DETECTION _Technical Root Causes System Root Causes

(PROTECT) ASPECT: WHY?

Use this path to Investigate why the

problem was PREDICT ASPECT :

Use these fields to investigate the systemic root cause

not detected WHY?

WHY? WHY? A

WHY? WHY?

WHY? WHY? C1

Ref. No. (RMA, DMR, etc)

… . WHY? B Date DD.MM.YYYY WHY?

Product / Process Location Content Latest Rev Date

Electrical component City/ Country DD.MM.YYYY

WHY? C2

Problem Resolution Complete

Communicate to Customer Date: DD.MM.YYYY

Process Change Break Point Date: DD.MM.YYYY

Implement System Change Date: DD.MM.YYYY

Lessons Learned: The template (word

or excel file) can be used as a

It is not mandatory to use exactly

this form, but it might be a help in tracing back the systemic root cause for both aspects,

non-conformance and non-detection.

Naze-Naze / 3x5Why-Analysis Template

Define Problem: TECHNICAL SYSTEM

ROOT-CAUSE ROOT-CAUSE

Result Investigation Report:

NON-CONFORMANCE (PREVENT): Use this path for the specific non-conformance b eing invested

Why? Why? Why? Why? Why?

NON-DETECTION (PROTECT): Use this path to investigate why the prob lem was not detected

Why? Why? Why? Why? Why? Why?

SYSTEM-ROOT CAUSE (PREDICT)

Use these fields to investigate the systemic or Management-Root Cause

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Naze-Naze / 3x5Why-Analysis Template

Naze-Naze / 3x5Why-Analysis Template

Naze-Naze / 3x5Why-Analysis

Thank you for your time.

Questions / Feedback: Mail to: [email protected] [email protected] [email protected] [email protected]