Why Why Analysis Training Material

3x5 Why-why Analysis - A new approach for root cause analysis

1st Supplier Quality Day * 27NOV09 ST Shenzhen Plant

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.

2

Naze-Naze / 3x5Why-Analysis Project Background

A. The Naze-Naze Project Background * Naze = “Why” in Japanese

3

Naze-Naze / 3x5Why-Analysis Project Background The Situation

寻根究底

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 scoring methodology 4

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

5

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.

6

B. The Naze-Naze Method

7

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 dated approximately 1390 AD. The earliest known written version of the rhyme above (often taught to British children)

8

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.

Mr.KAIZEN „Taiichi Ohno“ Ohno“ (1912(1912-1990) Former executive vice president of Toyota who established Toyota-ProductionSystem, 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

Having no problems is the biggest problem of all 9

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

10

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”.

11

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.

Then, describe “standard” and “actual” in comparison

Think from customer’s view 12

Naze-Naze / 5Why-Analysis Method Basics of Naze-Naze Analysis What to do

Grasp the situation Pursue root causes

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

Implement effective C/M Why to do

Grasp the pattern

Fix the real root cause and never let it reoccur 1. Shift from “reactive firefighting” to “preventive countermeasure”

C/M to prevent a reoccurrence

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

No reoccurrence should happen when the real root cause is fixed 13

Naze-Naze / 5Why-Analysis Method Grasp the situation accurately

Initial Problem Perception (large, vague or unclear) Clarify the problem

Shortcut to real root causes!

Preparation for 5 x Why 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

Locate the Point of cause

Locate the Point of cause

to clarify  what  when  where  who  how in GENCHI GENBUTSU 14

Naze-Naze / 5Why-Analysis Method

1

Clarify the problem

2

Locate the Point of cause

2

Point of cause

5 x Why is a key step in the problem solving

Basic Cause/Effect Investigation

Direct Cause

4

5 Why investigation

5

Root Cause

6

Countermeasure Follow Up and Check

CAUSE INVESTIGATION

3

GRASP THE SITUATION

Initial Problem Perception (large, vague or unclear)

把 握 真 实 情 况

进 行 原 因 调 查 分 析 Source: TMUK PPS

15

Naze-Naze / 5Why-Analysis Method Grasp the situation accurately ・・・ 1. Organize and narrow down the problem Often a detected failure is a combination of complex problems ＜Example＞ ＞ Contamination on a product

16

Naze-Naze / 5Why-Analysis Method Grasp the situation accurately ・・・ 2. Localize the problem Go back the processes from where the problem was detected ＜Example＞ ＞ Iron ball particle on a product

17

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.

Example

Email, letter, documents, etc…

le p m t Exa y char r o t s Hi

18

Naze-Naze / 5Why-Analysis Method Grasp the situation accurately ・・・ 3. Evaluate the situation, how the problem happened

19

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 20

Naze-Naze / 5Why-Analysis Method

21

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” Non-conformance

Non-detection

22

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.

Direct Cause 5 Why Investigation

Root Cause

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. 23

Naze-Naze / 5Why-Analysis Method Difference between “containment” and “preventive” measures ＜Example＞ ＞ Machine stop

24

Naze-Naze / 5Why-Analysis Method Difference between “Technical” and “System” root cause ＜Example＞ ＞ Machine stop

25

Naze-Naze / 5Why-Analysis Method Example entered into excel-template

26

Naze-Naze / 5Why-Analysis Method How Yokoten works in Toyota

*Depending on the severity, escalation level is decided.

水平扩展、 水平扩展、水平展开

Horizontal Deployment

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

27

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)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 ⑩ Read backwards and confirm if Naze-Naze story is correct

28

Naze-Naze / 5Why-Analysis Method ① Define “1st Why” from principle Principle: something very basic Focus on the problem phenomenon and define “1st Why” upon the principle of the problem Problem

1st Why

2nd Why

29

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 of 5Why.

30

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

No business can be continued with this root cause !

31

Naze-Naze / 5Why-Analysis Method ③ Verify the hypothesis as soon as a hypothesis is made • Verify the hypothesis immediately if possible, even during NazeNaze analysis. •

Verify by facts based on: SANGEN-SHUGI (Genba 现场, 现场 Genbutsu 现物, 现物 Genjitsu 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. These are all I need to see, to judge, to consider, to decide.

32

Naze-Naze / 5Why-Analysis Method ④ Do not diffuse the problem < Bad example > Motor overheate d

Insufficient lubricant

Avoid subjective issues, i.e. ＜Bad example＞ personal skills

The story was diffused due to missing description of what “insufficient” is Lubricant forgotten

Insufficient maintenance managemen t

Manager does not know GENBA

Wrong manager at the post

⑤ Avoid searching for causes under psychological aspects It is difficult to make effective countermeasures against mental to prevent reoccurrence < aspects Bad example > Why Mr.A got his head injured

Mr.A hit his head at the edge of the ceiling

Why

Why

C/M

Mr.A did not pay attention

Mr.A was careless

Be careful when walking

33

Naze-Naze / 5Why-Analysis Method ⑥ Describe simply + when, where, how, etc…

Describe simply with subject + verb

Do not describe two facts in one sentence （risk to miss other causes) < Bad example >

Only 1 subject in one sentence

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

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 Problem

Problem

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!

34

Naze-Naze / 5Why-Analysis Method ⑦ Avoid ambiguity Describe concretely Examples of inappropriate texts (to be avoided) XX is bad

XX is insufficient

Operator not enough experienced

XX shortage

XX not thoroughly done

X

Operator did not remember the changeover procedure

Describe concretely

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

The bolt diameter is big

XX is longer than YY

X

Bolt diameter is too big for the hole diameter The hole diameter is too small for the bolt diameter 35

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.

⑩ Read backward and confirm if Naze-Naze story is correct

36

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?

37

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 「Product C was mixed in product A」

38

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.

39

Naze-Naze / 5Why-Analysis Method Before you sign on a problem solving report: Go back with “therefore”

• 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? Mindset of coach

The reason that students (my colleagues) are not learning is because the teacher (I) is not teaching.

40

C. The 3 x 5Why-Focus

41

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: •

Because

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

•

Why

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).

42

Naze-Naze / 3x5Why-Analysis Focus Avoid this Pattern The following sequence of Questions should not be followed:

43

Naze-Naze / 3x5Why-Analysis Focus Basic Solution Pattern The following sequence of Questions is recommended:

44

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. 45

Naze-Naze / 3x5Why-Analysis Focus Summary Why-Why Analysis

Ask for system root causes for each technical root cause

non-detection: same as above! 46

D. Templates

47

Naze-Naze / 3x5Why-Analysis Template Naze-Naze / 5Why-Basic Word-Template Corrective Action with Responsibility

Define Problem

NONCONFORMANCE (PREVENT) ASPECT: Use this path for the specific nonconformance being investigated

Date

1 x 5Why :

A

DD.MM.YYYY

2 x 5Why :

B

DD.MM.YYYY

C1

DD.MM.YYYY

C2

DD.MM.YYYY

3 x 5Why :

WHY?

NON-DETECTION (PROTECT) ASPECT: Use this path to Investigate why the problem was not detected

Technical Root Causes

WHY?

System Root Causes PREDICT ASPECT : Use these fields to investigate the systemic root cause

WHY?

WHY?

WHY?

WHY?

A

WHY?

WHY?

WHY?

C1

WHY?

C2

Ref. No. (RMA, DMR, etc)

The template (word

.

…

or excel file) can be used as a Date

WHY?

DD.MM.YYYY summary sheet for root cause investigation. Product / Process

Location

B

WHY?

Content Latest Rev Date

It is not mandatory toCountry use exactly Electrical component City/ DD.MM.YYYY Communicate to Customer Date: DD.MM.YYYY this form, but it might be a helpProcess in Change tracing back Break Point Date: DD.MM.YYYY Problem Resolution Complete Implement System Change Date:

DD.MM.YYYY

Lessons Learned:root cause for both aspects, the systemic

non-conformance and non-detection.

48

Naze-Naze / 3x5Why-Analysis Template Define Problem:

TECHNICAL ROOT-CAUSE

SYSTEM ROOT-CAUSE

Result Investigation Report:

SYSTEM-ROOT CAUSE (PREDICT) Use these fields to investigate the systemic or Management-Root Cause

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

... Why?

Why?

e c x E

m e t l–

Why?

Why?

Why?

Why?

Why?

te a l p

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

Why?

Why?

Why?

Why?

49

Naze-Naze / 3x5Why-Analysis Template Example: Processability due to bad solderability

50

Naze-Naze / 3x5Why-Analysis Template Example: Weak Processability due to bad solderability (cont.)

51

Naze-Naze / 3x5Why-Analysis

Thank you for your time.

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

52