Originally called just-in-time (JIT) production, the Toyota Production System (TPS) is a socio-technical system that comprises management philosophy, practices, and technology.
The term “Lean” was associated with JIT production, by John Krafcik in his 1988 article, “Triumph of the Lean Production System“.
In 1996, James Woman and Daniel Jones furthered the evolution of Lean, with the 5 Principles of Lean Thinking.
The 5 Principles of Lean Thinking
- Identify value from the Customer’s perspective
- Goals? Jobs to be done? Pain points? Quantifiable?
- Map customer-specific value stream(s)
- What are the end-to-end activities?
- Align the value stream activities to provide the most efficient flow
- Time to Value (from the customer, to the customer)
- Supply only when there is real customer demand
- Reduce resource waste
- Strive for perfection by measuring and optimising flow
- Continually identify and minimise waste
The 8 Forms of Waste
| Defects Efforts caused by rework, scrap, and incorrect information | • Faulty or damaged products that have to be repaired or scrapped • Incorrectly completed application that has to be redone • Incomplete forms |
| Overproduction Production that is more than needed or before it is needed | • Making what you can • Producing reports that no one uses • Pushing work downstream before the next person is ready • Entering repetitive information |
| Waiting Wasted time waiting for the next step in a process | • Product in a work queue • Waiting for information, resources or approvals • Dependency on others to complete tasks • System response and down time |
| Non-Utilised Talent Non or underutilizing people’s talents, skills, and knowledge | • Not listening to team member’s improvement suggestions • Not doing an activity that should be done • Staff hired to do X but spending more time on Y • Underutilization of equipment (hardware, software, etc.) |
| Transportation Unnecessary movements of products and materials | • Moving the product from one location to another • Unnecessary information exchange between departments • Unorganized work spaces • Multiple handoffs |
| Inventory Building and storing extra materials/products than needed | • Extra stock in inventory in case of breakdown • Keeping several jobs open without completing any • Filing and storing the same document in multiple locations • Buying and storing more products, forms, and reports than needed |
| Motion Unnecessary movement of people that does not add value | • Looking in different locations to get information for one task • Poorly designed work environments • Searching for work documents and supplies • Frequency of trips to a copier or printer |
| Extra-Processing More work or higher quality than is needed by customer | • Running a small part on a large machine • Entering the same data into more than one system • Requiring too many signatures • Too much time spent on unnecessary task |
The benefits of Lean
- Improved customer relationship
- Increased quality
- Decreased operational costs
- Reduction of wasted work
- Increased throughput / productivity
- Increased efficiency
- A culture of continuous improvement
The limitations of Lean
- Perceived dehumanisation of work
- Increased level of stress due to striving for perfection
- Overly-focused on cutting waste
- Potential disagreement on what is waste
- Prioritisation of short-term efficiency gains can have negative long-term consequences