7 types of Waste

 Lean recognises 7 types of waste.

  • Waiting - The periods of inactivity in a downstream  process that occur because an upstream  activity does not deliver on time. Idle  downstream resources are then often used in  activities that either don’t add value or result  in overproduction.  This is often the result of  push based processes rather than pull.  In non-manufacturing environments and tasks this can be the literal waiting of people when a meeting is delayed in starting because a key or senior attendee is late, time lost when a person delays responding to an email or voicemail or time lost when a person has to locate the person they need to speak to.
  • Motion - Extra steps taken by employees and  equipment to accommodate inefficient  process layout, defects, reprocessing,  overproduction or excess inventory. Motion  takes time and adds no value to the product  or service. “To move and add value is called  work. To move and not add value is called  motion. Motion, then, means moving without  working, moving and adding cost”.
  • Transport - This is unnecessary motion or movement of  materials, such as work-in-process (WIP)  being transported from one operation to  another. Whilst some transport may be  inevitable it should be minimized for two  reasons; 1) It adds time to the process during  which no value-added activity is being  performed. 2) Handling damage could be  incurred.  Workstations should be as close  as possible to the ones that immediately  precede and succeed them, raw materials  and parts should be as close as possible to  the workstations that use them.
  • Extra Processing - Extra operations, such as rework,  reprocessing, handling, storage or  management that occurs because of defects,  overproduction or excess inventory.
  • Inventory - Excess stock that is not directly  required to fulfill current Customer orders.  Inventory includes raw materials,  work-in-process and finished goods. Inventory  also requires additional handling and space.
  • Defects - These are products or services that do not  conform to the specification or Customer’s  expectation, thus causing Customer  dissatisfaction.
  • Overproduction/Overwork - When operations continue to produce after  demand has been satisfied. The results of  overproduction are; Products being produced  in excess of what’s required.  Products being  made too early.  Excess inventory carrying  costs

Recently some training and consultancy vendors have added an 8th form of waste, 'Un-utilised People'.  This is differentiated from 'Waiting' (staff idle and not working) by concentrating on their skill sets.  A person might be fully utilised in terms of time and may be generating value but if they were enabled and supported to use their full skill set or a different part of their skill set then they could generate more value in the same time period.

Seven Types of Waste