Sadly when you search the lean manufacturing definition on many books , internet or even at the training courses , must of the time you find a very poor description of it ; many describe lean manufacturing as :
“…reduction of the seven wastes “Muda” to improve overall customer value”…..
However there are other 2 Ms that they forget to talk about , Mura and Muri , and basically on real life if we don’t reduce the 3 Ms the vicious cycle wont be reduced or eliminated.
“A partial truth is a lie” …. Up today “the lean fake” is very well implemented in many organizations and part of this; is the ignorance and the falsehood of Lean Manufacturing meaning.
The real secret of Toyota Production System is very simple reduce the 3M’s at the same time.
Since the beginning Toyota target to eliminate the 3M's, they were very aware if one of this M's remains the olds habits will be back.
The variation in work content or unevenness in flow resulting in needs to generate waste to manage it.
• Fluctuation in cycle time to complete a task
• Work content varies greatly by product model
• Unleveled production schedules
• Disruptions to operations: Set ups/breakdowns
• WIP and capacity are necessary to buffer out variability
• Conformance to pace is very difficult
• WIP decouples processes and hides problems
• Difficult to achieve throughput
The strenuous condition for both worker and machine as well as for the work processes.
• Fatigue issues, excessive lifting
• Ergonomic issues
• Operator must think to do it right
• Uncertainty of work content
• Reliance on human or stress on performance
• Excessive overtime
• Continuing to operate a machine with problems
• Defects and rework
• Buffer with inventories
• Employee injuries
• Morale and people discontent
• Late delivery of products/information
Activities, materials or information that do not contribute to the value creation of a product. Anything in excess of what is required to produced the desired result will either be a waste or generate waste.
Of all kaizen activities, Muda elimination is the easiest to start, as it is not difficult to identify muda once one has acquired such a skill. Muda elimination usually refers to stopping something that we have been doing up until now, and therefore costs little to implement. For these reasons, management should take the initiative in starting kaizen with muda elimination wherever they exist – in gemba, in administration, and/or in the area of service-providing.
If you just go for 1 M , you’ll never be successfully on your task, is easy Identify Muda but not Mura and Muri.