Christian HOHMANN

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Why this lean obsession about waste


Lean is about waste. Mainly about waste. Obsessive about waste.

Wastes are activities that carry costs without adding any value. Reducing wastes is turning these expenses into savings.
So far so good. Yet why doesn’t lean emphasize adding value instead?

Adding value means adding or improving something that customers will value and will be ready to pay for. It’s a real challenge because if such improvement or enrichment misses to convince the customers, the whole initiative is a waste. Adding value requires some ability to pick up the voice of customer and to design accordingly. This is a field devoted to marketing, design or R&D and their specialists.

Lean found its origins in Toyota’s workshops, where workers, techies and engineers had few if any opportunities to contribute to really add value. What they had plenty: wastes.

That’s probably the reason why Lean practitioners concentrated on wastes and keep doing so. Furthermore, wastes are everywhere and waste elimination can be challenged by everybody.

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Seeing only the tip of the iceberg

Strangely, if waste is everywhere, waste hunters sometimes miss to find them. In production / manufacturing, people often tend to improve what is already nearly optimum. Usually, value-added operations are already optimized, as they are long identified as critical to performance:

  • Cycle time
  • Yield
  • Man power
  • Scrap
  • etc.

Non value-adding operations keep being ignored even so they represent the biggest share. Only 1 or 2 % of the time a part spends in a workshop is used to add value as shown in this example of a mechanical part.

It took a total of 25 days for this part to complete its journey through the workshop, while being transformed or treated only a few minutes (0,2 day x 8 hours = approx 1,5 hour) in 14 different operations. It was picked up, moved and put down 84 times and traveled nearly 2km within the workshop, altogether with its sister parts in the same crate.

Aiming at the right target

The following scene shows a customer looking for fast served hot coffee. The whole process is made of coffee brewing followed by the delivery to customer.

The latter isn’t satisfied about performance, he’s waiting too long. As this complaint is common, management urges ops to improve the process.

Engineers look at the process and come up with a breakthrough solution; adding a turbocharger to the brewer, allowing the coffee to be ready for service in a tenth of usual time.

Despite this tremendous improvement, customers still aren’t happy with waiting time.

Management is furious about the investment, much too expensive for this result. Engineers are admonished to improve with cheaper means.

At least one of them remembers that transportation is a waste to be challenged, so they try low cost automation, providing waiters with rollers in order to minimize the duration of transportation. Alas this solution is not stable, many waiters fail to master the new process. The disruptions in service don’t help to increase customer satisfaction.

Seeing that engineers keep being irresistibly attracted by technological solutions, senior management fears another blunder with a time-warp machine or something of sorts and eventually hires an organization consultant.

The ultimate solution is as simple as reducing the waste itself by bringing production closer to consumption.


Opportunities for eliminating waste are far more numerous than opportunities to add value. Furthermore, anyone can reduce waste with little risk to make mistakes, while adding value is a matter for specialists. Value adding sometimes fails.

Mise à jour le Dimanche, 05 Janvier 2014 15:25