Definition
Work that consumes time, space, materials, capital, or people's energy without adding value the customer is willing to pay for, and is not currently necessary Non-Value Added activity.
In detail
Muda is the overarching concept in lean analysis and is not equivalent to the "Eight Wastes" checklist. The Eight Wastes is a memory framework that helps observers categorize and spot waste; actual Kaizen must still return to customer value, process purpose, and current constraints for judgment. You cannot automatically eliminate a task just because it does not directly process the product—for example, regulatory records may be Non-Value Added but currently necessary; the correct approach is to first distinguish Value Added, necessary Non-Value Added, and pure waste.
Example in practice
The team observed the order approval process and found that the same data was entered repeatedly by three departments, documents sat in email for two days, and approvers asked for information that already existed. Duplicate entry and waiting are Muda, but compliance signatures required by law are necessary non-value added. The Kaizen plan prioritizes eliminating duplication and waiting while simplifying rather than deleting compliance records.