Key takeaways
  • The eight wastes are transport, inventory, motion, waiting, overproduction, over-processing, defects and unused talent (TIMWOOD plus talent).
  • Overproduction is the most damaging because it creates the other seven.
  • You find waste by following one item through the process, not by asking people where the waste is.
The one to attack first
Overproduction, because it manufactures the rest

Making more than is needed creates inventory to store, transport to move it, waiting while it queues, and defects discovered long after the cause. Fix overproduction and several other wastes shrink without being addressed directly.

The eight, with what they look like

  • Transport. Moving material between buildings, or across a shop because two sequential operations are 40 metres apart.
  • Inventory. Racks of work in progress waiting for a bottleneck, or six months of a component bought for a price break.
  • Motion. An operator walking to a shared tool trolley twenty times a shift, or reaching across a bench for every part.
  • Waiting. A crew idle for a permit, an approval, a fork truck or a decision.
  • Overproduction. Running a batch larger than the order because the setup is painful.
  • Over-processing. Polishing a surface nobody sees, or three signatures where the risk justifies one.
  • Defects. Rework, scrap, and the inspection built to catch them.
  • Unused talent. The operator who knows why the machine drifts and has never been asked.

How to actually find them

Follow one item from arrival to despatch and record, honestly, every minute it is not being changed. The waiting and the transport become obvious quickly, and the exercise is more reliable than asking people, because everyone is blind to the waste they have normalised.

Which to fix in what order

  • Defects first if they reach the customer. Nothing else matters as much.
  • Then waiting at the bottleneck, because that is lost output you cannot recover.
  • Then overproduction, which usually requires fixing changeover time.
  • Motion and transport last, because they are visible and satisfying to fix but rarely the constraint.

The waste that is hardest to see

Unused talent, because it produces no pile in a corner. The signal is that improvement ideas only ever come from management, or that the same problem is discussed in meetings for a year while the person operating the machine could have explained it in a minute.