The TIMWOODS Method: How to Spot the 8 Types of Waste

Introduction: Why Waste Is Harder to See Than It Should Be

Most organizations agree that waste is part of their processes. The challenge is seeing it clearly and defining what exactly counts as waste. Over time, inefficiencies become normalised. Long walks, waiting for information, rework, excessive approvals, and overproduction are often seen as just the way things are here.

Lean challenges that assumption.

The TIMWOODS framework provides organisations with a shared language for waste, enabling teams to spot inefficiencies without assigning blame or engaging in debate. Instead of debating opinions, they assess processes based on clearly defined categories of non-value-added activities.

This blog details the TIMWOODS method, explaining why it remains one of the most effective waste-identification tools in Lean, and how to apply it as a practical improvement tool rather than just a theoretical checklist.

What TIMWOODS Really Represents

TIMWOODS is an acronym that represents eight essential types of waste present in nearly every organisation, regardless of industry.

Transportation
Inventory
Motion
Waiting
Overproduction
Overprocessing
Defects
Skills (Underutilized People)

Lean does not see these as just abstract ideas. Each category stands for the time, effort, or resources used that do not add value from the customer’s point of view.

Understanding TIMWOODS is important because it moves improvement discussions from blaming individuals to identifying where processes generate waste.

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Transportation: When Work Moves More Than Value Does

Transportation waste happens whenever materials, information, or work are moved more than necessary. Every move introduces risk, delay, and cost — yet transportation is often unseen because it seems productive.

Examples include moving parts between buildings, transferring paperwork for approvals, or handing work off between departments without adding value. Transportation does not improve the product; it merely relocates it.

Reducing transportation improves flow, shortens lead times, and lowers the risk of damage or miscommunication. Lean encourages organisations to ask: Why does this need to move at all?

Inventory: The Illusion of Security

Inventory is often seen as a buffer against uncertainty. While some inventory is necessary, too much inventory disguises problems instead of resolving them.

Excess inventory conceals quality problems, delays the identification of process failures, ties up cash, and takes up space. It also creates a false sense of stability, leading organizations to believe they are prepared when they are actually disconnected from real demand.

Lean considers inventory as excess waste — a sign of imbalance between demand and flow. Lowering inventory makes issues more visible, which can be uncomfortable initially but is vital for growth.

Motion: Effort Without Progress

Motion waste refers to unnecessary physical movement by people. Excess reaching, bending, walking, searching, or repositioning adds effort without adding value.

Unlike transportation, which moves the product, motion moves the worker. Over time, excessive motion causes fatigue, increases injury risk, and decreases consistency.

Lean concentrates on designing work to ensure that necessary tools, parts, and information are readily available at the point of use. When motion is minimized, both productivity and safety are enhanced.

Waiting: When Flow Stops

Waiting waste happens when people, materials, or information are idle because of imbalance or delay. Workers wait for instructions, machines wait for parts, approvals wait in inboxes, and customers wait for delivery.

Waiting is often the most obvious waste but the least challenged because it seems unavoidable. Lean teaches that waiting usually results from poor coordination, unclear priorities, or uneven workloads.

Lowering wait times enhances responsiveness and shows how well the system is synchronized.

Overproduction: The Most Dangerous Waste

Overproduction happens when work is finished sooner, faster, or in larger amounts than the customer needs. It is the most harmful type of waste because it causes other wastes — inventory, motion, waiting, and defects.

Overproduction is often caused by local efficiency metrics that reward utilisation rather than flow. Lean counters this by aligning production with actual demand.

Providing exactly what is needed, when it is needed, is not slower — it is more precise.

Overprocessing: Doing More Than the Customer Values

Overprocessing waste occurs when processes include steps that do not add value from the customer\’s perspective. Extra inspections, redundant approvals, excessive documentation, or unnecessary precision all fall into this category.

While overprocessing often stems from good intentions, it wastes time and resources without adding value. Lean encourages teams to ask: Would the customer pay for this step if they saw it?

Removing overprocessing simplifies tasks and accelerates workflow.

Defects: The Costliest Waste

Defects cause waste through rework, scrap, delays, and lost trust. Even minor defects ripple through the system, using capacity that could be better employed elsewhere.

Lean considers defects as process failures rather than individual errors. The focus is not on identifying who caused the defect, but on understanding what enabled it to happen.

Reducing defects enhances cost, delivery, and morale all at once.

Skills: The Most Underestimated Waste

The final “S” in TIMWOODS — underutilized skills — is often overlooked. When people’s ideas, experience, and problem-solving abilities are ignored, organisations lose their most powerful improvement resource.

This waste occurs when employees are confined to task execution without involvement in improvement, decision-making, or learning. Lean focuses on engaging people to identify waste because those closest to the work see it most clearly.

Respect for people is integral to Lean — it is fundamental.

Using TIMWOODS as a Daily Lens

TIMWOODS is most effective when used regularly, not sporadically. Lean organisations incorporate it into process walks, team discussions, and improvement activities.

Instead of starting large projects right away, teams use TIMWOODS to ask targeted questions.

Where are we waiting?
What are we moving unnecessarily?
Which steps exist only because of past problems?

Over time, this common language fosters alignment and speeds up improvement.

Why TIMWOODS Supports Culture Change

TIMWOODS removes emotion from waste discussions. Instead of criticizing behaviour, teams evaluate processes based on objective categories. This reduces defensiveness and encourages collaboration.

When waste identification becomes regular and safe, improvement no longer feels like criticism but rather progress.

Conclusion: Waste Identification Is the Starting Point, Not the Goal

TIMWOODS does not eliminate waste on its own — it raises awareness. Awareness encourages better questions, conversations, and decisions.

Organizations that regularly use the TIMWOODS approach incorporate improvement skills into their daily routines. They cease accepting inefficiency as standard and begin designing processes that value time, effort, and people.

Waste exists in every system.
Lean methodology succeeds when waste is made clearly visible.