Understanding Value, Waste, and the Seven (Plus Eighth) Types of Waste in Lean Manufacturing

Value and Waste – Taiichi Ohno, the father of the Toyota Production System, emphasized the importance of going to the shop floor to observe value and waste directly, arguing that real insight comes from first‑hand experience.

Value is defined as the characteristics of a product or service that satisfy customer requirements and for which customers are willing to pay, including functional, quality, and cost aspects. Delivering the right thing the first time also represents value. Value‑added activity is a process that physically or chemically transforms a product to meet those requirements, requiring both that the product’s features meet customer needs and that a physical or chemical change occurs.

Muda, Mura, and Muri – In Lean terminology, three phenomena cause organizational pain: Muda (waste), Mura (unevenness), and Muri (overburden). Muda refers to any activity that does not add value. Muri describes a state of excessive load on people, machines, or systems, leading to stress and inefficiency. Mura denotes irregular or unbalanced workflows that disrupt smooth production.

These three are interrelated: Mura is the root cause, which creates Muri, and together they generate Muda. Eliminating any one of them can remove the others.

An illustrative example shows three transportation plans for moving six tons of material: a single overloaded truck creates Muri (overburden) and consequently Muda and Mura; a two‑trip plan creates Mura (uneven deliveries) and also Muri and Muda; a three‑trip plan avoids Mura and Muri but still incurs Muda due to under‑utilized loads. The optimal solution is two trips of three tons each, matching the truck’s rated capacity and eliminating all three wastes.

The Seven Classic Wastes – Lean identifies seven types of waste: (1) overproduction, (2) defects, (3) waiting, (4) unnecessary motion, (5) transportation, (6) over‑processing, and (7) excess inventory. Each waste is described with examples such as producing more than demand, producing defective parts, machine downtime, inefficient motions, unnecessary moving of materials, processing steps that do not affect quality, and excessive stock that incurs holding costs.

The Eighth Waste – Beyond the tangible wastes, Lean also highlights a hidden waste: the failure to utilize employees’ creativity, ideas, and skills, which occurs when organizations do not involve or listen to their workforce.

References – The concepts are drawn from James Womack and Daniel Jones’ works on Lean thinking and terminology, as well as a Zhihu article (https://zhuanlan.zhihu.com/p/28403056).

Certification Promotion – The article concludes with a notice about the FDCC (Fundamental DevOps Capability Certification) white‑belt program, offering a limited‑time free exam for those who follow the public account and reply “FDCC”. It lists the required courses, experience, and exam criteria.