Lean + AI Glossary

Every Lean Six Sigma and AI term we use — explained in plain language. Built for operations leaders who want to understand before they implement.

5 Whys

A root-cause technique: ask 'why?' repeatedly (about five times) until the underlying cause surfaces.

5S

Workplace organization method: Sort, Set in order, Shine, Standardize, Sustain — the foundation of operational discipline.

5W2H

A structured problem framework: What, Why, Where, When, Who, How, How much.

AI Agent

An AI system that can plan and take multi-step actions toward a goal — Gartner predicts 40% of agentic projects cancelled by 2027.

AI Readiness

The degree to which a company's processes, data, systems and people are prepared to adopt AI successfully.

AI Readiness Assessment

A structured evaluation scoring how prepared an organization is for AI across operational dimensions, before investing.

Bottleneck

The slowest step that limits the throughput of the whole process — the constraint to address first.

Change Management

The structured approach to helping people adopt new processes and tools — the human side that makes AI stick.

COPIS

SIPOC filled in reverse, starting from the Customer — ensures the process is designed around real customer value, not internal habit.

Cycle Time

The time a process step is actively worked on, excluding waiting — a key VSM metric.

Data Quality

How accurate, complete, consistent and timely data is — Gartner attributes 85% of AI project failures to poor data.

Data Readiness

Whether data is clean, accessible, labeled and structured enough to train or feed AI reliably.

Digital Transformation

Reworking processes, culture and technology to deliver value in a digital-first way — not just buying software.

DMAIC

Define, Measure, Analyze, Improve, Control — the core Six Sigma project methodology for reducing defects.

DOWNTIME (8 wastes)

Acronym for the 8 Lean wastes: Defects, Overproduction, Waiting, Non-utilized talent, Transportation, Inventory, Motion, Excess processing.

Gemba

Japanese for 'the real place' — going to where the work actually happens to observe and improve it directly.

Generative AI

AI that creates new content (text, images, code) — MIT found 95% of enterprise GenAI pilots show no P&L impact.

Heijunka

Production leveling — smoothing volume and mix to avoid peaks and troughs that create waste.

Hoshin Kanri

Policy deployment — aligning every level of the organization to a few breakthrough strategic goals.

Jidoka

Automation with a human touch — machines stop automatically when a defect occurs so problems are fixed at the source.

Just-in-Time (JIT)

Producing only what is needed, when needed, in the amount needed — minimizing inventory waste.

Kaizen

Japanese for continuous improvement — small, incremental changes made constantly by everyone, rather than rare big leaps.

Kanban

A visual system that signals when to produce or move work, limiting work-in-progress and exposing bottlenecks.

KPI (Key Performance Indicator)

A measurable value showing how effectively a goal is being achieved — used to track transformation progress.

Large Language Model (LLM)

An AI model trained on vast text that generates and understands language — the engine behind tools like ChatGPT.

Lead Time

Total elapsed time from when an order is placed to when it is delivered, including all waiting.

Muda

Japanese for waste — any activity that consumes resources but adds no value the customer would pay for.

Muri

Japanese for overburden — overloading people or equipment beyond reasonable limits, a cause of breakdowns and errors.

Non-Value-Added (NVA / NNVA)

Steps that add no value; NNVA is necessary for now (compliance, control), pure NVA is waste to be eliminated.

Operational Excellence

A culture where every employee can see value flow and fix problems — the mature end-state Lean aims for.

PDCA

Plan-Do-Check-Act — the iterative improvement loop for testing changes before scaling them.

Poka-Yoke

Mistake-proofing — designing a process so that errors are impossible or immediately obvious.

Process Mining

Using event logs from IT systems to automatically reconstruct and analyze how processes actually run.

RAG (Retrieval-Augmented Generation)

An AI pattern that grounds a language model in your own documents, reducing hallucination and improving accuracy.

ROI (Return on Investment)

The financial return of an initiative relative to its cost — central to justifying AI and Lean projects.

RPA (Robotic Process Automation)

Software 'bots' that automate repetitive, rule-based digital tasks like data entry and re-keying.

SIPOC

A high-level process map listing Suppliers, Inputs, Process, Outputs, Customers — a one-page picture of any process used in the Define phase of Lean Six Sigma.

Social Network Analysis (SNA)

Mapping the informal communication networks in an organization to reveal brokers, bottlenecks and how work really flows.

Standard Work

The current best, documented way to perform a task — the baseline that makes improvement and automation possible.

Takt Time

The pace of production needed to match customer demand — total available time divided by customer demand.

Theory of Constraints (TOC)

A method that improves throughput by finding and systematically removing the single biggest constraint.

Value Stream Mapping (VSM)

A visual map of every step in a process showing value-add time vs waste, used to redesign workflows toward smooth flow.

Value-Added (VA)

A process step the customer would willingly pay for because it transforms the product or service toward what they want.

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