Six Sigma + Lean Manufacturing Study Library

History of Six Sigma Study-ready

Where Six Sigma came from, how belt training emerged, how GE scaled it, and how professional Bodies of Knowledge (BoK) evolved — so belt study sits in context. See Toyota & TWI for how TWI entered Toyota after WWII, and TWI & Job Instruction for how standards are taught.

Timeline — development of training

Pre-1980s foundations

Statistical process control (SPC) and the control chart tradition (Shewhart) and Deming/Juran quality management set the analytic culture Six Sigma later packaged.
ASQ’s broader History of Quality timeline situates Six Sigma inside a century of industrial quality practice.
Training lineage: WWII U.S. TWI → postwar GHQ introduction in Japan → Toyota JI/JM/JR adoption (1950s) shaped how Lean plants teach and improve standards (see TWI section / lean-six-sigma/twi-toyota.html).

1986 — Motorola invents Six Sigma

Engineer Bill Smith at Motorola formalizes a defect-reduction / variation-control approach labeled Six Sigma (commonly dated 1986); CEO Bob Galvin sponsors the quality push.
Goal: drive processes toward roughly 3.4 defects per million opportunities (DPMO) when the classic 1.5σ shift convention is applied.
Motorola builds internal curricula and practitioner qualifications; wins Malcolm Baldrige National Quality Award (1988).
Mikel Harry and others help spread the martial-arts-inspired belt vocabulary (Green/Black/Master Black) as a training and deployment system.

1990s — GE and Fortune 500 scale

Jack Welch makes Six Sigma a GE corporate initiative (mid-1990s), tying training, projects, and leadership expectations to business results.
AlliedSignal/Honeywell and others adopt similar programs; by late 1990s a large share of Fortune 500 firms run Six Sigma-style initiatives.
Belt roles harden: Champions sponsor; Black Belts lead complex projects; Green Belts lead scoped projects part-time; Yellow/White expand awareness and team support.

2000s — Lean Six Sigma + professional BoKs

Lean (waste/flow, with deep Toyota/TPS roots) merges with Six Sigma (variation/defects) as Lean Six Sigma in many plants.
Professional bodies (notably ASQ) publish belt certifications with explicit Bodies of Knowledge; IASSC and free primers (CSSC) also shape study paths.
DMAIC remains the workhorse for improving existing processes; DFSS/DMADV grows for new product/process design.
Training implication: belts are a capability ladder — vocabulary → team contribution → project leadership → coaching/advanced stats.

Q&A study cards

Q1. Who is credited with originating Six Sigma at Motorola?

A. Engineer Bill Smith (mid-1980s, commonly 1986), with CEO Bob Galvin’s sponsorship. Mikel Harry helped productize training and the belt system.

Q2. Why did GE matter historically?

A. Jack Welch’s mid-1990s corporate mandate scaled Six Sigma from a quality method into an enterprise training + project system that other firms copied.

Q3. Where did the belt names come from?

A. Martial-arts-inspired ranks for practitioner depth (White/Yellow awareness and support; Green project lead; Black coach/complex lead; Master Black program/strategy), popularized through Motorola-era training design and later industry programs.

Q4. What is a Body of Knowledge (BoK) here?

A. A published outline of what a certified belt should know (topics + cognitive levels). ASQ Green/Black BoKs are the common professional reference; IASSC and CSSC also publish study frameworks.

Q5. How did Lean and Six Sigma come together?

A. Lean (TPS-rooted waste/flow) and Six Sigma (variation/defects) were combined in the 2000s as Lean Six Sigma so plants attack both muda and process noise.

Q6. DMAIC or DFSS — which is the historical default?

A. DMAIC for improving an existing process is the classic Six Sigma project path; DFSS/DMADV grew for designing new products/processes to Six Sigma performance.

Q8. How does History connect to TWI on this site?

A. Six Sigma history explains belt training; Toyota & TWI explains postwar adoption and JI→SW / JM→kaizen / JR→leadership; TWI/JI explains the instructional method itself — foundations before White→Black study.

Q9. Why study History before belts?

A. So belt labels read as a capability ladder with real origins — not fashion badges — and so BoK expectations make sense.

Q10. Where does Toyota/TWI sit vs Six Sigma history?

A. TWI arrived in Japan in the late 1940s–50s and shaped Toyota supervisor training long before Motorola (1986). Belts are a later quality/project ladder; JI is how standards get taught.

Q11. JI / JM / JR → TPS in one line?

A. JI teaches standardized work; JM feeds kaizen/method improvement; JR supports respect/leadership — the people OS that helped TPS stick.

Toyota & TWI Study-ready

How Toyota absorbed Training Within Industry after WWII — and how the three J programs map onto TPS training culture: Job Instruction → standardized work, Job Methods → kaizen mindset, Job Relations → respectful leadership.

Timeline — TWI into Toyota / TPS training

1940–1945 — TWI in the U.S.

U.S. War Manpower Commission creates Training Within Industry to develop supervisors for wartime production.
Three core “J” programs: Job Instruction (teach), Job Methods (improve), Job Relations (lead people).
Credo of JI: “If the worker hasn’t learned, the instructor hasn’t taught.”

1947–1950 — TWI enters Japan; Toyota crisis

TWI programs are introduced to Japanese industry during the postwar occupation (Civil Communications Section / Economic & Scientific Section channels).
Isao Kato recalls introduction around 1947–48; LEI/Huntzinger and Art of Lean also document Lowell Mellen / TWI, Inc. installation work ~1949–51 and national multiplier spread.
1950: Toyota near bankruptcy; management–union agreements include a demand for better supervisor development.
Toyota HR evaluates existing programs and adopts TWI as the vehicle for first-line supervisor training.

1951–1953 — JI, JM, JR roll out at Toyota

Dec 1951 — Job Instruction (JI) introduced (~300 trained in the first wave) — Isao Kato / Art Smalley interview notes (LEI PDF).
Jun 1952 — Job Methods (JM) introduced.
Mar 1953 — Job Relations (JR) introduced.
Taiichi Ohno is aware of TWI and himself trains the material; he especially values JI for multi-process handling and teaching as takt changes.

Mid-1950s onward — JM → P-Course → kaizen; JI sticks

Ohno finds JM too narrow for the waste / flow / takt thinking he wants; JM is eventually dropped as a standalone course.
Shigeo Shingo’s industrial-engineering “P-Course” (production/productivity) helps replace JM for engineers and supervisors.
Toyota later builds internal Standardized Work and Kaizen courses (drawing on Ohno, Shingo’s P-Course, surviving JM elements such as 5W1H, and training-department design).
JI remains in Toyota essentially unchanged; JR stays nearly intact (case studies updated). Toyota also develops Job Safety (JS).

Legacy — people development as TPS DNA

Kato’s framing: you cannot separate people development from production-system development.
Toyota saying: mono zukuri wa hito zukuri — “making things is about making people.”
LEI / Art of Lean: JI is still a primary training tool for Toyota team leaders; standardized work defines the method, JI teaches it.

JI · JM · JR → TPS training culture

Job Instruction (JI) → Standardized work / training to standard

Four steps: Prepare → Present → Try out → Follow up.
Job Breakdown Sheet: important steps, key points, reasons why — the trainer’s teaching script.
Standardized Work Chart shows takt, work sequence, and standard in-process stock; JI is how humans learn to perform that method.
Accountability: if the worker hasn’t learned, the instructor hasn’t taught (process over blame).
Toyota internal adaptation often called TJI (Toyota Job Instruction); modern skills dojos keep the essence.

Job Methods (JM) → Kaizen / improvement mindset

JM teaches supervisors to break down the present method, question every detail (5W1H), then Eliminate / Combine / Rearrange / Simplify (ECRS).
Aim: greater quantity of quality product in less time by better use of people, machines, and materials — small incremental gains from the floor.
At Toyota, JM was a starting influence but too shallow for Ohno’s waste/flow/takt vision; replaced by Shingo’s P-Course, then internal Kaizen + Standardized Work training.
Surviving DNA: questioning every detail and involving the people who do the work — the kaizen mindset.

Job Relations (JR) → Respectful leadership / people problems

JR lays groundwork: trust, cooperation, treating people as individuals, informing about change, constructive feedback.
Problem pattern: get the facts → weigh and decide → take action → check results.
NIST MEP: positive relations make JI and JM work — people who care about doing the job properly.
At Toyota, JR was well received and remains nearly intact as supervisor training (cases updated).

Study checklist

JI → standardized work: Job Breakdown (steps / key points / reasons) underpins teaching the current best method; SW chart defines takt, sequence, standard WIP — the document does not teach the job
JM → kaizen: Job Methods’ 5W1H / ECRS improvement questioning seeds continuous improvement; Toyota deepens it into waste elimination, flow, and internal kaizen / SW courses
JR → leadership: Job Relations builds trust, fairness, and a facts-based way to handle people problems — respectful leadership that makes JI and kaizen stick
Postwar path: occupation-era transfer → 1950 Toyota adoption → 1951–53 JI/JM/JR → JM replaced; JI/JR endure
Isao Kato (“father of standardized work and kaizen courses”) and Art Smalley interviews as primary historical witnesses
Ohno’s role: valued JI for multi-process handling and training to changing takt; frustrated with JM’s shallow scope
Practical rule for plants today: improve the method (kaizen), lock the standard (SW), teach it with JI, lead people with JR habits
Cross-link: Six Sigma History explains belt training; Toyota & TWI explains how Lean standards are taught and sustained

Plant takeaway

JI → standard work: define the method, then teach it with breakdown + four steps.
JM → kaizen: question every detail; Toyota deepened this into waste/flow kaizen courses.
JR → leadership: trust and fair people-problem handling so instruction and improvement stick.
Primary witnesses: Isao Kato + Art Smalley (LEI / Art of Lean).
Deep page: lean-six-sigma/twi-toyota.html · method detail: TWI & JI.

Q&A study cards

Q1. When did Toyota adopt TWI?

A. After evaluating programs during the 1950 crisis, Toyota rolled out JI (Dec 1951), JM (Jun 1952), and JR (Mar 1953). TWI had already entered Japan around 1947–48.

Q2. How does JI connect to standardized work?

A. Standardized work defines the current best method (takt, sequence, standard WIP). JI is the method for teaching that work — via breakdown sheets and Prepare/Present/Try out/Follow up. The posted chart does not teach the job.

Q3. Did Job Methods become kaizen?

A. JM’s questioning habit (5W1H / ECRS) influenced improvement culture, but Ohno found JM too shallow for TPS waste/flow/takt thinking. Toyota replaced JM with Shingo’s P-Course and later internal Kaizen + Standardized Work courses — that is the JM → kaizen lineage.

Q4. What did Toyota keep from JR?

A. Respectful, facts-based handling of people problems. JR was well received and remains nearly intact as supervisor training (cases updated) — the leadership foundation under JI and kaizen.

Q5. Which TWI program mattered most to TPS?

A. Per Isao Kato (and Ohno’s emphasis): Job Instruction — by far. It enabled job breakdown, four-step teaching, and skills matrices needed as Ohno spread multi-process handling and changing takt.

Q6. Is TWI “the roots of Lean”?

A. Kato: TWI strongly shaped supervisor training and influenced kaizen courses, but it is not the overall roots of TPS — takt, flow, pull, jidoka, kanban, etc. came from Toyota. TWI is a critical people-development root, not the whole tree.

Q8. What is mono zukuri wa hito zukuri?

A. Toyota saying: “making things is about making people.” TWI (especially JI/JR) is a practical starting point for building that capability at the supervisor level.

Q9. Plant takeaway in one line?

A. Kaizen improves the method → standardize it → teach it with JI → lead the people side with JR habits — or gains walk out the door with the project lead.

TWI & Job Instruction (JI) Study-ready

Training Within Industry (TWI) — especially Job Instruction (JI) — is the WWII-era method behind much of Toyota’s how-to-train DNA and modern train-the-trainer (TTT) practice. Postwar GHQ introduced TWI in Japan; Toyota mapped JI→standardized work/training, JM→kaizen/process improvement, JR→respect/leadership. Pair with belt study: belts solve problems; JI teaches the standard so gains stick. Deep page: lean-six-sigma/twi-toyota.html.

Q&A study cards

Q1. What is TWI in one sentence?

A. A WWII U.S. supervisor-training system (especially JI, JR, JM) for teaching jobs, improving methods, and leading people — later foundational for Toyota-style operator training.

Q2. What are the four JI steps?

A. Prepare the learner, Present the operation, Try out performance, Follow up — always in that order, with major steps, key points, and reasons.

Q3. How does JI connect to Toyota / TTT?

A. Toyota adopted TWI postwar; JI underpins teaching standardized work. Train-the-trainer programs inherit the same idea: develop people who can instruct correctly, safely, conscientiously.

Q4. Where do belts and JI meet on a project?

A. After Improve, Control should leave a Job Breakdown + trained instructors — otherwise the new method dies when the Green Belt walks away.

Q5. JI vs Job Methods — difference?

A. JI teaches the current best way; JM questions and improves the way the job is done. Use both: improve, then instruct.

Q6. Why not just “watch Joe for a week”?

A. Shadowing skips key points and reasons, varies by trainer, and hides safety/quality tricks. JI makes instruction deliberate and repeatable.

Q8. Where is the Toyota adoption story on this site?

A. In the Toyota & TWI section (bridge between History and TWI): timeline 1947–53, JI→SW / JM→kaizen / JR→leadership, and Kato/Smalley sources.

Q9. JR in one sentence for a team leader?

A. Treat people as individuals; get the facts; weigh and decide; take action; check results — so the team trusts you enough for JI and kaizen to work.

Q10. How did TWI get to Japan / Toyota?

A. GHQ/occupation authorities (ESS and related channels) introduced TWI to rebuild industry; Lowell Mellen / TWI, Inc. helped install programs (~1949–51). Toyota adopted JI/JM/JR in the early 1950s as supervisor skill infrastructure.

Q11. What did Toyota take from JI, JM, and JR?

A. JI → teach standardized work (Job Breakdown + four steps). JM → floor-owned method improvement / kaizen habit (later deepened beyond classic JM). JR → facts-based people-problem leadership aligned with respect for people.

Q11. Is TWI the root of Lean / TPS?

A. It is a major root of Lean training and supervisor development, and it influenced kaizen habits — but not the full TPS toolset (flow, pull, jidoka, etc.). Isao Kato (LEI): underappreciated for people development; not the whole of Lean.

Q12. How does TWI relate to train-the-trainer culture?

A. TWI’s design was the multiplier: develop a standard method, then train people who train others. Modern TTT and Control-phase JI handoffs inherit that architecture.

White Belt Study-ready

Awareness-level introduction to Lean and Six Sigma vocabulary, roles, and why factories care about waste and variation. Includes brief history/TWI awareness. Study-ready for floor leaders and new CI participants.

Q&A study cards

Q1. What is the difference between Lean and Six Sigma?

A. Lean removes waste and improves flow/speed. Six Sigma reduces variation and defects with data. Many plants use both as Lean Six Sigma.

Q2. What does a White Belt typically do?

A. Learn vocabulary, support team norms (5S, waste awareness), and participate when asked — not lead DMAIC projects alone.

Q3. What is DMAIC?

A. Define, Measure, Analyze, Improve, Control — the structured problem-solving roadmap for improving an existing process.

Q4. What is a defect in Six Sigma terms?

A. Any output that fails a customer or specification requirement — counted relative to opportunities (DPMO thinking).

Q5. Name common Lean wastes.

A. Transportation, Inventory, Motion, Waiting, Overproduction, Overprocessing, Defects (TIMWOOD); often plus Skills underutilization.

Q6. How does 5S help a factory?

A. It makes abnormal conditions visible, cuts search/motion waste, and builds the discipline needed for standard work and kaizen.

Q7. What is 6S?

A. 5S plus Safety — organize the workplace so abnormal conditions and hazards are visible and controlled; it is a common training extension, not a claim that Toyota renamed 5S.

Q8. What is CTQ?

A. Critical-to-Quality — the measurable characteristics that matter most to the customer for a product or process.

Q9. How does this connect to Toyota / TPS?

A. TPS pillars Just-in-Time and Jidoka, plus kaizen and standardized work, are the roots of much of modern Lean practice.

Q10. Why do belts exist historically?

A. Motorola-era training used ranked ‘belt’ roles so organizations could build project leaders and coaches — not only run one-off classes.

Q11. What is Job Instruction in one line?

A. TWI’s four-step method to teach a job correctly and consistently — the training half of standardized work.

Yellow Belt Study-ready

Team-member level: contribute to improvement projects, collect data, apply basic Lean tools, follow DMAIC with coaching, and support Job Instruction / standard work on the floor.

Q&A study cards

Q1. What does a Yellow Belt do on a project?

A. Supports Define/Measure work: maps process, gathers data, joins root-cause sessions, and helps pilot improvements under Green/Black guidance.

Q2. What is a SIPOC used for?

A. A one-page scope tool showing Suppliers, Inputs, Process, Outputs, and Customers so the team agrees on boundaries early.

Q3. When should you use 5 Whys vs a fishbone?

A. 5 Whys drills one causal chain deeply; a fishbone brainstorms many possible cause categories before focusing.

Q4. What is takt time?

A. Available production time divided by customer demand rate — the ‘heartbeat’ that paces Lean flow.

Q5. Why collect a baseline before Improve?

A. Without Measure, you cannot prove the change worked or detect backsliding in Control.

Q6. What is a kaizen event?

A. A short, focused improvement burst (often days) that implements visible Lean changes with the people who do the work.

Q8. How does Yellow Belt relate to train-the-trainer?

A. Yellow Belts can reinforce standard work and waste awareness on the floor — useful assistants when trainers roll out new processes with JI.

Q9. What belongs in a simple control plan?

A. What to measure, how often, who reacts, reaction rules, and where standards live after the project ends.

Q10. Pareto in one sentence?

A. Focus on the vital few causes or defect types that drive most of the pain (~80/20 thinking).

Q11. What are Important Steps vs Key Points in JI?

A. Important Steps are the logical chunks of the job; Key Points are what make or break quality/safety/ease — with Reasons explaining why.

Green Belt Study-ready

Study-ready. Leads scoped DMAIC projects part-time: tollgates, MSA/Gage R&R intro, capability, basic hypothesis tests & regression orientation, FMEA, VSM/Lean flow tools, and Control handoff with standard work / JI. Escalate heavy DOE to Black Belt.

DMAIC tollgates

Define

Measure

Analyze

Improve

Control

Q&A study cards

Q1. How is Green different from Yellow?

A. Greens lead scoped DMAIC projects and own Measure/Analyze rigor (MSA, capability, verified causes); Yellows primarily support data and team work.

Q2. What is a DMAIC tollgate?

A. A phase-exit review with the sponsor/coach: evidence that exit criteria are met before burning effort on the next phase.

Q3. Why MSA before trusting data?

A. If the gage or method is noisy, you will ‘improve’ measurement noise instead of the process — fix the measurement system first.

Q4. Stable vs capable — what’s the difference?

A. Stability (in statistical control) means predictable common-cause variation. Capability asks whether that stable process fits customer specs (Cp/Cpk).

Q5. Cp vs Cpk in one line?

A. Cp is potential capability if centered; Cpk penalizes off-center location versus the nearer spec limit.

Q6. When do you use a hypothesis test as a Green?

A. To confirm a suspected difference or effect with data (e.g., before vs after, line A vs B) — interpret p-values with practical significance and sample-size humility.

Q8. What is regression orientation at Green depth?

A. Use scatter/correlation and simple models to quantify Y = f(X); watch residuals and don’t overfit. Multi-factor optimization → Black Belt.

Q9. When escalate DOE to Black Belt?

A. Multi-factor interactions, fractional designs with confounding, response-surface optimization, or when experimental risk/cost is high.

Q10. What belongs in a Green Belt control plan?

A. CTQ/process measures, method & frequency, who reacts, reaction rules, where standards/JI live, and audit cadence.

Q11. How does JI show up in Control?

A. Update the Job Breakdown (steps/key points/reasons) and train with Prepare–Present–Try out–Follow up so the new method survives shift changes.

Q11. What is process FMEA for?

A. Prioritize failure modes before launching a change and after redesign — drive actions on severity, occurrence, and detection, not paperwork scores alone.

Q12. VSM at Green depth — what must you capture?

A. Material + information flow, inventories, C/T, C/O, uptime, lead time vs process time, then a future state with pull/WIP limits and kaizen bursts.

Black Belt Study-ready

Study-ready. Dedicated CI leader: complex DMAIC, coaching Greens through tollgates, full DOE & regression leadership, advanced MSA, portfolio/Hoshin link, Lean system design, and DFSS awareness — multiplying capability, not hero-solving alone.

DMAIC tollgates

Coach — Define

Coach — Measure

Coach — Analyze

Coach — Improve

Coach — Control

Q&A study cards

Q1. What is a Black Belt’s primary job?

A. Lead complex improvements, coach other belts, and protect method quality through tollgates — multiplying capability, not just running tools.

Q2. DMAIC vs DFSS?

A. DMAIC improves an existing process; DFSS/DMADV designs a new process or product for Six Sigma performance when redesign-from-scratch is the need.

Q3. Why limit project portfolio WIP?

A. Too many concurrent projects stall finishes. Throughput of completed, controlled improvements rises when WIP is capped.

Q4. What makes a good tollgate question?

A. Evidence-seeking and coach-like: ‘Show the MSA decision,’ ‘Which Xs are verified?,’ ‘Who owns the JI update?’ — not ‘Did you fill the template?’

Q5. Full vs fractional factorial — when?

A. Full factorials estimate all interactions but grow fast with factors. Fractionals reduce runs but confound effects — Black Belts must explain the tradeoff.

Q6. How do you use regression as a Black Belt?

A. Build explanatory/predictive Y = f(X) models, check residuals and collinearity, and translate coefficients into process setpoints — then verify on the floor.

Q8. How does Hoshin link to Six Sigma projects?

A. Hoshin (catchball, breakthrough objectives) selects and aligns the portfolio so Black Belt effort serves strategy, not local hobby projects.

Q9. How does Black Belt support factory training / TTT?

A. Turns project learnings into standard work and trainer-ready Job Breakdowns so JI instructors can teach the new method across shifts.

Q10. When is advanced MSA worth the cost?

A. When CTQs are high-risk, gages are borderline, tests are destructive/nested, or capability claims will drive customer or launch decisions.

Q11. OFAT vs DOE — coaching line?

A. One-factor-at-a-time misses interactions and wastes runs. If multiple Xs may interact, plan a designed experiment.

Q11. What is leader standard work for a Black Belt?

A. A personal cadence of gemba, tollgate coaching, portfolio review, and audit of standards — modeling the system you ask others to sustain.

Q12. Heijunka at Black depth — why care?

A. Leveling volume/mix stabilizes upstream and labor; without it, pull systems and standard work thrash under batch spikes.

Six Sigma + Lean Manufacturing Study Library

History of Six Sigma Study-ready

Timeline — development of training

Pre-1980s foundations

1986 — Motorola invents Six Sigma

1990s — GE and Fortune 500 scale

2000s — Lean Six Sigma + professional BoKs

Study checklist

Why it matters here

Recommended reading / links

Q&A study cards

Q1. Who is credited with originating Six Sigma at Motorola?

Q2. Why did GE matter historically?

Q3. Where did the belt names come from?

Q4. What is a Body of Knowledge (BoK) here?

Q5. How did Lean and Six Sigma come together?

Q6. DMAIC or DFSS — which is the historical default?

Q8. How does History connect to TWI on this site?

Q9. Why study History before belts?

Q10. Where does Toyota/TWI sit vs Six Sigma history?

Q11. JI / JM / JR → TPS in one line?

Toyota & TWI Study-ready

Timeline — TWI into Toyota / TPS training

1940–1945 — TWI in the U.S.

1947–1950 — TWI enters Japan; Toyota crisis

1951–1953 — JI, JM, JR roll out at Toyota

Mid-1950s onward — JM → P-Course → kaizen; JI sticks

Legacy — people development as TPS DNA

JI · JM · JR → TPS training culture

Job Instruction (JI) → Standardized work / training to standard

Job Methods (JM) → Kaizen / improvement mindset

Job Relations (JR) → Respectful leadership / people problems

Study checklist

Plant takeaway

Recommended reading / links

Q&A study cards

Q1. When did Toyota adopt TWI?

Q2. How does JI connect to standardized work?

Q3. Did Job Methods become kaizen?

Q4. What did Toyota keep from JR?

Q5. Which TWI program mattered most to TPS?

Q6. Is TWI “the roots of Lean”?

Q8. What is mono zukuri wa hito zukuri?

Q9. Plant takeaway in one line?

TWI & Job Instruction (JI) Study-ready

Core topics checklist

Key tools

Recommended reading / links

Q&A study cards

Q1. What is TWI in one sentence?

Q2. What are the four JI steps?

Q3. How does JI connect to Toyota / TTT?

Q4. Where do belts and JI meet on a project?

Q5. JI vs Job Methods — difference?

Q6. Why not just “watch Joe for a week”?

Q8. Where is the Toyota adoption story on this site?

Q9. JR in one sentence for a team leader?

Q10. How did TWI get to Japan / Toyota?

Q11. What did Toyota take from JI, JM, and JR?

Q11. Is TWI the root of Lean / TPS?

Q12. How does TWI relate to train-the-trainer culture?

White Belt Study-ready

Core topics checklist

Key tools

Recommended reading / links

Q&A study cards

Q1. What is the difference between Lean and Six Sigma?

Q2. What does a White Belt typically do?

Q3. What is DMAIC?

Q4. What is a defect in Six Sigma terms?

Q5. Name common Lean wastes.

Q6. How does 5S help a factory?

Q7. What is 6S?

Q8. What is CTQ?

Q9. How does this connect to Toyota / TPS?

Q10. Why do belts exist historically?

Q11. What is Job Instruction in one line?

Yellow Belt Study-ready

Core topics checklist

Key tools