The Meaning of “Waste” in Lean Manufacturing

In lean manufacturing, we consider “waste” as any operation that does not add value to the customer. In other words, waste reduces profits, therefore, customers do not want to pay for it. Lean manufacturing seeks to eliminate waste from your process, thus improving profits and optimizing processes. The result of eliminating waste? A higher-quality product for the customer. In this article, we will help you identify the eight wastes of lean manufacturing so that you can remove them from your process.

The Eight Wastes:


We call product defects to the need to completely scrap or send back a product. Defects represent a loss of time, money, and resources. Besides, if a manufactured product possesses defects, the customer’s satisfaction will be reduced. This type of waste can occur, for instance, due to poor quality controls during the manufacturing process or inaccurate inventory levels. Therefore, this costs more time and money because of the need to re-manufacture the product.

Tip: Make sure quality standards are met all along the manufacturing process to reduce this type of waste.


Manufacturing more products than the ones needed. Here we have a waste of time and a need for extra resources, such as workers to stock the products. This can occur due to inaccurate information regarding customer demand or delayed set-up times.

Tip: You can establish a pull system so that you only manufacture as many goods as needed to meet customer demand.


Waiting mostly has to do with equipment idle time and bottlenecks within the manufacturing process. Time is money, so, the amount of time spent not producing is considered waste. Furthermore, piles of products can build up and create bottlenecks if the timing of the different manufacturing stages is inappropriate. For instance, if a station takes longer to produce a part, there will be a bottleneck because each part that arrives to the station will have to wait longer, and it will take longer to process each of them.

Tip: If you accurately measure takt time, you will reduce this type of waste.

Non-Utilized Employees

This waste involves assigning the wrong tasks to employees or having employees who are not trained for a certain task. This type of waste may also be the result of poor management of communication. You need to train people so they can identify issues and generate improvement ideas.

Tip: If you provide operators with training and growth opportunities, overall operational effectiveness will improve. Making them experts in what they do will help them make sure nothing is overlooked.


Moving materials and parts around the plant can lead to waste, especially if the factory’s layout has been poorly designed. Unnecessary product transportation leads to wasted time. This type of waste can also occur if you overproduce certain goods, since you need multiple large storage facilities to store them.

Tip: Rearrange the factory’s layout so that the different stages of production flow. Do a Spaghetti diagram to visualize possible flows of operators, tools, inventory, equipment, or products.


We consider any supply in excess as waste since you need space to hold overproduction. If there were no extra products, that space could be put to better use. To this storage costs, we must add the extra transportation cost that it takes to move these products from the station to the storage facility.

Tip: Analyze material flow and storage limits, only purchase raw materials when needed and in the amounts needed. If you do this, you will prevent overproduction, thus reducing inventory waste.


The motion of people, equipment, and raw materials costs money. We consider as waste any movement that does not add value to the customer, for instance, if an operator bends or lifts a part.  The lean manufacturing methodology looks for a proper facility layout and optimized workplace design which includes the analysis of the distance of motion within the space as well as the location of parts, supplies, and tools within the space.

Tip: After watching the operator in action, organize the workstation in such a way that equipment and tools are near the production locations.

Extra Processing

This waste signals a poor process design. It includes any effort that adds no further value to the product. This type of waste can occur due to lack of communication, duplication of data or human errors.

Tip: Always question the need for any of the current steps in your manufacturing process. If it is not essential, get rid of that step.

How to Eliminate Waste With 4i Platform

You must have a complete overview of your manufacturing process to identify and eliminate waste. With 4i Platform, visualize what’s going on at your plant in real time. Our data analysis will allow you to discover you hidden factory and it will show you which machines and manufacturing stages need improvement so that you can optimize your manufacturing process.

<<Benefit from 4i Platform and learn how to make data-driven decisions to reduce waste and improve efficiency>>  

About the Author

Santiago Picco

Partner @ 4i Platform - Data Driven Innovation Electronic Engineering specified in control automation. Master in Stategic Management of Techology. Data scientist. Industry 4.0. IIoT and Digital transformation.

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