Waste is any use of resources that does not create value for the customer.
Lean commonly groups waste into eight categories. The framework is useful because it helps teams observe processes more systematically instead of relying only on intuition.
A common memory aid is TIMWOODS.
Transportation
Unnecessary movement of materials, products or information between locations.
Examples include excessive forklift travel, repeated transfers between departments or sending information through avoidable handoffs.
Inventory
More raw material, work in process or finished goods than the process currently needs.
Inventory can hide quality problems, delays, unreliable processes and poor production control.
Motion
Unnecessary movement by people or equipment while performing work.
Searching, reaching, bending, walking and repositioning are common forms of motion waste.
Waiting
Time when people, materials, equipment or information are ready but cannot proceed.
Waiting often appears around approvals, machine cycles, breakdowns, missing information and unbalanced processes.
Overproduction
Producing earlier, faster or in greater quantity than downstream demand requires.
Overproduction is especially damaging because it can create additional inventory, movement, storage and quality problems.
Overprocessing
Doing more work than the customer or process requires.
Examples include duplicate data entry, unnecessary inspection, excessive precision or repeated approvals.
Defects
Errors that create rework, scrap, sorting, delays, complaints or additional inspection.
The visible defect is often only part of the loss. Defects also consume capacity and management attention.
Skills
Failing to use people’s knowledge, capability and ideas effectively.
This waste may appear when employees are excluded from problem solving, poorly trained, assigned work below their capability or unable to influence the processes they understand best.
Use the framework at Gemba
The 8 Wastes are most useful when applied to actual work.
Observe the process directly. Follow a product, service, person or piece of information. Ask where time, movement, effort and capacity are being consumed without creating value.
The framework should help teams see problems, not become a checklist exercise.
Waste depends on the process
The eight wastes are categories for observation, not a scoring system.
The same activity can have different meaning depending on the process. Moving a patient for necessary treatment is not automatically transportation waste. Moving the same patient repeatedly because information or equipment is unavailable may be.
Teams should therefore examine why the activity exists and whether it contributes to the required outcome.
Waste can hide other waste
One form of waste often protects the process from another problem.
Excess inventory may hide unreliable equipment. Extra inspection may compensate for an unstable process. Waiting may result from poor balance or missing information.
Removing the visible waste without understanding the condition underneath can expose the process to failure.
That is useful if the team is ready to solve the underlying problem, but harmful if the organization simply removes the buffer and increases pressure.
Overproduction deserves special attention
Overproduction is often considered particularly damaging because it creates or amplifies other wastes.
Producing earlier or in larger quantities than needed increases inventory, handling, storage, waiting and the risk that defects travel farther before detection.
Reducing overproduction usually requires better flow, smaller batches, reliable processes and a clear connection to customer demand.
The goal is not merely less inventory. It is a production system that responds more closely to actual need.