[Complete Explanation] Toyota Production System (TPS): Eliminating Waste While Improving Quality and Speed — Implementation Guide for Just-in-Time / Jidoka / Andon / Kanban / A3

Key Points (Summary)

• The core of TPS rests on two pillars:
  ① Just-in-Time (JIT) — deliver the necessary items, at the necessary time, in the necessary quantity.
  ② Jidoka (Autonomation) — a mechanism that allows people to “stop” production to prevent defects from spreading.
  Running beneath these pillars is Kaizen (continuous improvement) as the underlying rhythm.
• Order over tools: focus on sequence — standardized work → visualization → small improvements to build “flow,” followed by Heijunka (leveling) and Kanban for total optimization.
• Practical tools ready for use: Andon (visualizing abnormalities), Takt time management, U-shaped layout optimization, A3 problem-solving (Gemba × Root cause analysis), 5S, and 5 Whys.
• Who is it for? Not just manufacturing — also call centers / back offices / development & operations. Any workplace with a process can apply it. Replace inventory = work-in-progress / task backlog, and service industries can improve in the same way.
• Accessibility: Display indicators, abnormalities, and procedures without relying on color, clarify reading order and alternative text, and ensure all applications and forms are fully keyboard-operable, creating an environment where anyone can “stop” the process.

Introduction — “The Courage to Stop” Enables Both Quality and Speed

TPS is not a mere collection of techniques. It is a culture that visualizes waste, stops abnormalities on the spot, and fixes them at the site.

• Just-in-Time creates “flow.”
• Jidoka serves as a “brake” that prevents defect propagation.
• Kaizen becomes the “daily muscle” that moves you forward millimeter by millimeter.
  As a result, wastes such as inventory, waiting, transportation, and overprocessing are reduced, bringing you closer to faster, more stable, and higher quality performance.
  Instead of relying on complex analysis, TPS emphasizes Genchi Genbutsu (go and see the real place, the real thing) and continuous small corrections — this is the heartbeat of TPS.

1. The Two Pillars of TPS in 3 Minutes

1-1. Just-in-Time (JIT)

Deliver only what is needed, when needed, in the amount needed. This involves:

• Takt time (rhythm aligned to customer demand)
• Heijunka (leveling) (smoothing daily workload)
• One-piece flow / small lot size (reducing WIP = inventory)
  The narrower the flow, the faster problems surface, making them easier to fix.

1-2. Jidoka (Autonomation)

Give machines the ability to think autonomously, and give humans the right and duty to stop.

• Andon (signals abnormalities with light and sound visible to all)
• Poka-yoke (designs to prevent or contain mistakes)
• Stop and prevent recurrence (halt the line to address root causes)
  The key mindset shift: “Stopping is not bad”; rather, “letting defects pass is bad.”

2. Applying TPS to Services and Offices

• Inventory = unprocessed tickets / approvals / pull requests
• Work-in-progress = customer waiting time, employee task load
• Takt = processing capacity per hour/day/week
• Andon = pre-SLA violation alert lights or dashboard indicators (red/yellow/green)
• Poka-yoke = mandatory form checks, automatic template substitutions
  By translating manufacturing terms into your local workplace language, TPS becomes immediately usable.

3. Improvement Is 90% About Order — Safe Implementation Roadmap (30-60-90 Days)

Day 1–30: Visualize Current State (Safety First)

1. Value vs. Waste Map: Draw the process as a SIPOC-style diagram (Customer → Input → Process → Output → Customer).
2. Takt and Capacity: Compare daily demand (input) and throughput (output) to find bottlenecks.
3. Standard Work Sheet (v1): One page (A4) outlining steps → time → safety → quality checks, including reading order and alternative text.
4. Light 5S: Sort → Set in order → Shine. Use color + text + icons for labels.

Day 31–60: Create Small Flows

1. One-piece-flow Cells: Arrange into U-shaped layouts where feasible (inlet and outlet close).
2. Andon Rules: Clearly define stop criteria (when/who/how to stop) and restart conditions.
3. Kanban (pull signal): The next process pulls only what it needs; even a whiteboard is fine.
4. Heijunka: Smooth unevenness by adjusting order timing or batch size.

Day 61–90: Standardization → Institutionalize Learning via A3

1. Standard Work Sheet (v2): Update to reflect reality; include alt text and reading order.
2. A3 Problem Solving: Use one A3 (or two A4 pages) with: Background → Current state → Goal → Cause → Countermeasure → Result → Horizontal deployment.
3. Daily Kaizen: Use the 5 Whys for root cause; implement one small improvement per week consistently.

Guideline: Always prioritize Safety → Quality → Delivery → Cost. Even when pursuing speed, never sacrifice safety or quality — that’s TPS etiquette.

4. Ready-to-Use Templates (Copy-Paste OK)

4-1. Standard Work Sheet (A4, Inverted Triangle, Reading Order)

1. Summary (3 lines): Process name / Takt / Safety notes
2. Procedure (numbered): Each step with time, key points, inspection points
3. Quality Check: Define criteria with text + icons, not color alone
4. Exceptions and Stop Criteria (Andon): Conditions to stop, restart conditions, contact info
5. Visual Aids: Photos/diagrams (alt text required)

4-2. A3 Problem Solving Sheet

• Background: Why this issue matters (customer, safety, cost)
• Current State: Quantitative (graphs) + Qualitative (on-site voice)
• Goal: Target level and deadline (e.g., takt, defect rate, wait time)
• Cause Analysis: Fishbone diagram / 5 Whys
• Countermeasures: Who, when, cost, expected effect
• Results: Numeric changes and side effects
• Horizontal Deployment: Templates and training for reuse

4-3. Andon Operation Card

• Abnormality Type: Quality / Safety / Equipment / Materials / Information
• Who Can Stop?: Everyone (even newcomers)
• How to Stop: Button / chat command (keyboard-accessible)
• Restart Conditions: Checklist completion and supervisor confirmation
• Record: Time, place, cause, countermeasure (voice input → auto transcription possible)

5. Field Examples (3 Cases)

Case 1: Assembly Line (Manufacturing)

• Issue: WIP pileups, many defects found at inspection stage
• Action: U-shaped layout + one-piece flow; redesign standard work to match takt = 60 sec; use Andon for torque abnormalities.
• Result: Inventory −35%, reinspection −40%, line stops increased but zero defect outflow.

Case 2: Call Center (Service)

• Issue: Flat first-call resolution (FCR), long queues at peaks
• Action: Visualize takt = avg. handling time per case; standardize script (“summary → confirmation → guidance”); Andon = pre-SLA alert with text + icon, not just red color.
• Result: FCR +6pts, avg. wait time −22%, training time −15%.

Case 3: Back Office (Accounting)

• Issue: Month-end payment backlog
• Action: Split submission deadlines with Heijunka; Poka-yoke for input (digits, mandatory fields, formats); A3 to explore delay causes.
• Result: Backlog −50%, rework −60%, zero extension requests.

6. KPI Design — “Outcome × Speed × Stability × Learning × Fairness”

• Outcome (Lag): Defect rate, FCR, reinspection rate, CSAT, inventory/WIP days
• Speed (Flow): Takt adherence rate, lead time, median processing time
• Stability (Quality): Median Andon duration (alert → resolved), recurrence rate
• Learning (Reuse): # of A3s, # of standard work revisions, training video plays
• Fairness (Culture): Distribution of “who stopped the line” (new hires, contractors, departments), adoption rate of anonymous feedback

Visualization Tips: Use color + labels + icons, include text summaries, specify reading order, and ensure keyboard-only dashboard control.

7. Common Pitfalls and Gentle Countermeasures

• “Reduce inventory” leads prematurely
  • Fix: Start with takt and standard work; cutting inventory without stable flow causes chaos.
• “You’ll get scolded if you stop” culture
  • Fix: Praise those who stop. Share good stop examples weekly and standardize restart criteria.
• Improvement depends on individuals
  • Fix: Document in A3 → share; turn success into reusable templates.
• 5S turns into cleaning events
  • Fix: Quantify goals like reduced search time or fewer safety risks.
• Color-only alerts
  • Fix: Ban “red only.” Use text + icons + sound for universal recognition.

8. Accessibility-Centered TPS — “A Workplace Anyone Can Stop”

• Inverted-triangle documents: Summary → Main text → Supplement, allowing busy or screen-reader users to grasp key points in one minute.
• Specified reading order: Clearly define heading levels and order in standard work, A3s, and dashboards.
• Color independence: Use color + label + icon for Andon, SLA, and quality results.
• Keyboard operation: Ensure Andon alerts, records, and approvals work without a mouse.
• Alternative text: Add short explanations for images, diagrams, and control charts.
• Plain Japanese (“Yasashii Nihongo”): Use short sentences / bullet points / furigana for readability.
  These practices enhance quality and safety while accommodating diverse visual, auditory, attention, and language needs.

9. Easy “Mini TPS” (Start Tomorrow)

1. Today’s Andon: Agree on 3-line stop criteria within your team.
2. Tomorrow’s 5S: Organize to cut 5 minutes of search time.
3. This Week’s A3: Tackle one theme in two A4 pages (Current → Cause → Countermeasure).
4. Next Week’s Leveling: Smooth workload peaks in 30-minute increments.
5. Month-End Standard Revision: Release v2 in local language — aim for a “living standard,” not perfection.

10. Who Benefits Most? (Examples)

• Manufacturing (plant managers, maintenance): Combine Andon + one-piece flow for zero defect outflow; takt + standards reduce training cost.
• Customer Service / Call Centers: Visualized takt × standard scripts × SLA Andon enable “no waiting” operations.
• Development / Operations (SaaS, IT): Treat WIP = unmerged PRs; improve flow through Heijunka and Pull systems.
• Back Office (Accounting / HR): Distribute month-end workload via Heijunka; Poka-yoke reduces rework.
• Public / Healthcare / Education: Identify “waiting” at the Gemba, and foster organizational courage to stop via Andon.

11. Summary — “Stop, See, Fix” Is the Shortest Path

TPS is a daily discipline that reduces inventory and waiting, achieving both quality and speed.

1. Create flow with Just-in-Time.
2. Prevent defect outflow through Jidoka (Andon, Poka-yoke).
3. Build learning assets through A3 and 5S.
4. Make Accessibility the standard so anyone can stop the process.

Rather than large investments, start with “3-line stop criteria today” and A3 (2-page) problem solving. Small steps are fine — together, let’s nurture a quiet yet powerful flow.