{"id":"seven-wastes","model_id":"7 Wastes","name":"7 Wastes","summary":"The 7 Wastes is Taiichi Ohno's categorization of seven major wastes typically found in mass production: overproduction, waiting, conveyance, processing, inventory, motion, and correction. It is used to identify non-value-creating activities and to distinguish waste from value-creating and incidental work.","study_notes":["The seven wastes are overproduction, waiting, conveyance, processing, inventory, motion, and correction.","Overproduction is producing ahead of what is actually needed by the next process or customer; the document calls it the worst form of waste because it contributes to the other six.","Waiting is operators standing idle as machines cycle, equipment fails, or needed parts fail to arrive.","Conveyance is moving parts and products unnecessarily, such as from a processing step to a warehouse and then to a subsequent processing step when the second step could be adjacent to the first.","Processing is performing unnecessary or incorrect processing, typically from poor tool or product design.","Inventory is having more than the minimum stocks necessary for a precisely controlled pull system.","Motion is operators making movements that are straining or unnecessary, such as looking for parts, tools, or documents.","Correction is inspection, rework, and scrap.","Two categories of work are value-creating work, which is directly necessary for making products, and incidental work, which must be performed but does not create value from the customer's standpoint.","Waste is motions that create no value and can be eliminated, such as walking to get parts or tools that could be positioned within reach.","Type one muda creates no value but is unavoidable with current technologies and production assets; an example is inspecting welds to ensure they are safe.","Type two muda creates no value and can be eliminated immediately; an example is disconnected steps in process villages that can be reconfigured into a cell."],"safety_notes":[],"sources":[{"url":"https://www.lean.org/lexicon-terms/seven-wastes/","title":"What are the 7 Wastes in Lean? | Lean Enterprise Institute","accessed":"2026-10-25"},{"url":"https://www.lean.org/lexicon-terms/waste/","title":"Waste - Lean Enterprise Institute","accessed":"2026-10-25"}],"verification":{"status":"source_checked","checked_at":"2026-10-25","values":2,"method":"llm_source_check"},"updated_at":"2026-10-25","type":"operational","spec":{"kind":"methodology","origin":"Taiichi Ohno","related":[]},"url":"https://machineschema.com/operational/seven-wastes","license":"https://creativecommons.org/licenses/by/4.0/"}