Wastes of LEAN

BAY MING JIAN

— 2 min read
Share

The 8 Wastes of Lean, Applied to Warehousing

TIMWOODS is easy to recite and easy to misapply. Here is each waste with a warehouse-floor example and the first countermeasure worth trying.

Most operators can recite the eight wastes — Transport, Inventory, Motion, Waiting, Overproduction, Overprocessing, Defects, Skills — long before they can spot them in their own building. The gap is usually that the textbook examples are generic and the floor is not. Below is each waste mapped to what it actually looks like in a distribution centre, plus one countermeasure to start with.

Transport

Not the trucks — the internal movement of goods between receiving, storage, and pack-out. A pallet that gets put away, then relocated, then picked, then staged has moved four times before it ever left the building. Track distance travelled per SKU for your top 20 movers; the fix is almost always a slotting problem, not a labour problem.

Inventory

Excess stock hides every other problem — a slow receiving process, unreliable suppliers, poor demand forecasting — behind a buffer. It also ties up cash and warehouse space that should be earning their keep. Ask what would break if safety stock were cut by 20% for 90 days; the answer tells you which upstream process actually needs fixing.

Motion

The picker's walk path, not the pallet's. In a poorly slotted warehouse, pickers can spend more time walking than picking. A simple spaghetti diagram of one picker's shift is usually the fastest way to convince a sceptical operations manager that slotting is worth revisiting.

Waiting

Dock doors idle because appointments weren't staggered. Pickers idle because the WMS release wave hasn't fired. Waiting is invisible on a P&L line but shows up directly in throughput per labour hour — the metric that actually matters to a shift supervisor.

A waste you can't see on the floor is a waste you'll never eliminate from a spreadsheet.

Overproduction & Overprocessing

In a DC, overproduction is picking or packing ahead of the actual outbound schedule — work-in-process that looks like progress but just becomes tomorrow's clutter. Overprocessing is double-checking, double-scanning, or double-labelling because two systems don't trust each other's data. Both usually trace back to a broken handoff between two teams or two systems, not to anyone working carelessly.

Defects & Skills

Defects are the obvious one — mis-picks, damaged goods, wrong labels — and DIFOT (delivered in full, on time) is the metric that captures their downstream cost. Skills waste is the quieter one: your most experienced picker knows three workarounds that never made it into a standard operating procedure, so the knowledge leaves when they do.

Where to start

  • Pick one waste, not eight. A team chasing every waste at once fixes none of them well.
  • Measure before you fix. A five-minute gemba walk with a stopwatch beats an assumption every time.
  • Fix the handoff, not the person. Most floor-level waste is a symptom of a system or process gap upstream.