The 8 wastes (TIMWOODS)

Identifying Waste in Your Process

Lean methodology identifies eight types of waste — activities that consume resources but create no value for the customer. The mnemonic TIMWOODS helps you remember them.

T — Transport

Unnecessary movement of materials or products between locations. On a value stream map, look for long arrows between stages or stages that are geographically distant.

I — Inventory

Excess raw materials, work-in-progress, or finished goods. Shown as triangles on the VSM. Inventory hides problems and ties up cash.

M — Motion

Unnecessary movement of people — walking, reaching, bending. Not visible on a standard VSM but can be noted in stage observations.

W — Waiting

Idle time when work is not being processed. On the VSM timeline, waiting time is the gap between value-added activities. This is usually the largest waste.

O — Overproduction

Making more than the customer needs, or making it too early. Overproduction drives all other wastes because excess output must be transported, stored, and managed.

O — Over-processing

Doing more work than necessary — higher precision, extra features, or redundant inspections that the customer does not value.

D — Defects

Producing output that requires rework or is scrapped. On the VSM, look for rework loops or stages with low first-pass yield.

S — Skills (underutilised talent)

Not using people's knowledge, creativity, and experience. The eighth waste was added more recently and reminds us that process improvement requires everyone's input.

Using TIMWOODS with MapVS

When analysing your value stream map, go through each stage and ask: which of these eight wastes exist here? MapVS analytics can automatically flag some wastes (waiting time, inventory levels) but others require human observation during Gemba walks.