Taiichi Ohno, a Japanese industrial engineer, is regarded as the founder of the Toyota Production System. Ohno discovered seven lean wastes (Muda in Japanese) in manufacturing processes while looking for better ways to optimise resources (the 8th waste was added in the 90s).
The 8 wastes are known as TIMWOODS —
- Transportation
- Inventory
- Motion
- Waiting
- Overproduction
- Over-Processing
- Defects
- Skills
The 8 waste methodology was initially designed for the automotive industry. However, as time passed, multiple industries across the vertices began to use it to add value to business processes.
We will examine each of these wastes in detail below:
1) Transportation
The waste of transportation is the moment of people, tools, inventory, equipment, or products in access. It’s the excess moment of resources being utilized for the customers first-hand. In any business process, there happens to be the shortest transport distance. Having to move work in process from department to department when simpler production compositions are available, the process is considered to be a waste.
2) Inventory
Sometimes it gets tough to think of inventory in excess as waste. It’s because inventory is considered an asset. But inventory in excess is a waste for sure! It can create problems such as greater lead times in the production process, inefficient allocation of resources, defects or damage to materials and problems hidden in the inventory that take longer to surface. Excessiveness can be caused by over-purchasing of raw materials and supplies, overproducing of work in process by having long queues, or producing more product than the customer’s requirement.
3) Motion
This type of waste is the unnecessary movement of people, machinery, or equipment. This includes walking, lifting, reaching, bending, stretching, and moving. To reduce this kind of waste, tasks that require excessive motion should be redesigned to enhance the work of personnel and increase the health and safety levels.
4) Waiting
Waiting time is often caused by halts and jump points in the production stations and can result in excess inventory and overproduction. Waiting waste can also be generated by upstream processes that are unpredictable due to disruptions or quality issues.
The waste of waiting for includes:
1) People waiting on material or equipment
2) Idle equipment
Countermeasures to reduce Waiting waste include:
- Designing processes to ensure continuous flow or single piece flow
- Levelling the workload by using standardized instructions
- Developing flexible multi-skilled workers according to work demands
Read all of the 8 wastes in detail here: https://www.6sigma.us/lean-six-sigma-articles/lean-the-8-wastes/