Lean – Muda, Muri, and Mura
In the area of Lean, we talk about “the 3 M:s” (Muda, Muri, and Mura) as the causes of waste and loss. The simplest one to grasp is Muda, that classifies the activities that do not add value and thus constitute waste if they are carried out. In the original classification, there are 7 Muda categories.
Transport, Stock, Movement, Waiting, Over-production, Over-work, Defects
There are several tried and proven methods and tools for decreasing waste in the 7 Muda categories, and this is described in detail in the literature on Lean.
Harder to access and less described are Muri, which is an overload of staff members or equipment, and Mura, which is an uneven load or uneven flow. The root cause of the waste that is seen in the 7 Muda categories often comes from Muri and Muda. In the case of uneven and thus from time to time low load (Mura), there is a tendency to over-produce and over-work and thus build unnecessary stock. Note that uneven load is both a question of variation over time and of the load being unevenly allocated among the resources. Irrespective of origin, the negative consequences are the same. In the case of overload (Muri), the likelihood increases for defects and unnecessary transfers and movements, at the same time as queues create unnecessary waiting time and more WIP (stock).
A very effective way of decreasing waste in a project organization is to first and foremost focus on decreasing Muri and Mura, resulting in a dramatic decrease in the 7 Mudas.
Decreasing Muri and Mura is a question of starting projects in the right pace and with the right mix. Velocity from VMG is tailor-made for this purpose. With Velocity from VMG, it is easy to spot when a critical capacity becomes available and to compare the load created by various project mixes on the organization over time.