The 8 Wastes of Lean (DOWNTIME): What They Look Like in an Indian Factory

What are the 8 wastes of Lean?

The eight wastes of Lean are Defects, Overproduction, Waiting, Non-utilised talent, Transportation, Inventory, Motion and Extra-processing. The first letters spell DOWNTIME. Waste is any work, in the shop or the office, that uses time, money or effort but that the customer does not pay for.

Every factory owner has heard "reduce waste". But when we ask, "Where is the waste in your plant?", many owners say, "We have very little. We use everything."

That is because waste does not look like waste. It looks like normal work. The operator walking to the tool room looks busy. The rework bench looks like quality. The extra stock looks like safety. Once you can name the eight wastes, you can start to see them.

What is waste, in simple words?

Use one test for every activity: is the customer paying for this?

The customer pays for real work, such as turning, milling, welding or assembly. Everything else uses time and money without changing the product. Some of it is necessary, like safety checks. But most of it can be reduced.

Waste is not only scrap and dust. It is also unwanted activity. Walking, waiting, searching and re-entering data are waste too.

The eight wastes, one by one

Each waste has its own article in this series, and each has its own short video. The first one, on defects, is linked at the top of this page.

Which wastes cause the others?

The wastes are connected. Overproduction leads to excess inventory. Excess inventory leads to waiting, because parts queue and the real job is stuck behind them. Extra parts also need moving and searching, so transportation and motion grow.

Defects hide in the same pile. When you make a big batch before checking, a small fault becomes a big loss.

This is why overproduction is called the worst waste. It quietly feeds all the others.

Waste is never one person's mistake. It is built into the way the work is set up.

Where does waste really come from?

Waste (the Japanese word is muda) rarely comes alone. It usually follows two other problems.

• Mura, uneven work. The shop is slow for three weeks, then rushes in the last week to dispatch.
• Muri, overload. People work double shifts. Machines run without daily checks. Nobody has time to check the first piece.
• Muda, waste. Breakdowns, rejections and rework follow. The next month starts with repairs.

So if you only remove the waste you can see, it comes back next month. You must also even out the work and stop overloading people and machines.

How do we find waste in a plant?

The simplest method is a waste walk. Take a notebook and walk the path of one order, from the material store to dispatch. Do it slowly, with the supervisor.

1. Walk in the order the work flows, not department by department.
2. At each step, ask: is the customer paying for this?
3. Write down every wait, every move, every pile, every re-check.
4. Mark each note with the letter of the waste, D, O, W, N, T, I, M or E.
5. Count the minutes or the quantity, even roughly.

Do not look for who is at fault. Look at the process. Nobody is doing anything wrong on purpose.

How to start in your plant

1. Pick one product that moves through many departments.
2. Do the waste walk in the first week and list at least ten wastes.
3. Rank them by cost in time or money.
4. Choose the top two and fix the cause of each, not only the symptom.
5. Walk again after a month and count again.

Play the video: Defects in Manufacturing: The Most Expensive Waste