Lean – aka Toyota Production System (TPS) – invented by Taiichi Ohno:
- Lean evolved at Toyota over the last 50 years – its goal is to eliminate waste and continuously improve productivity in every area of work, including customer relations, product design, supplier networks and factory management
- Wikipedia says Lean aims ‘to produce less low-value human effort, less inventory, less time to develop products, and become highly responsive to customer demand while producing top quality, error-proofed products in the most efficient and economical manner’
- There are five principles which define the Lean process:
- Provide what the customer wants, defect free
- Provide what’s required on demand, exactly as requested
- Provide an immediate response to problems or required changes
- Provide what’s required with a minimum of waste
- Provide what’s required safely, both for the customer and the supplier
- Lean is said to address seven deadly wastes:
- Overproduction – production getting ahead of demand
- Transportation – moving things unnecessarily
- Waiting – for the next production step
- Inventory – when not being processed
- Motion – moving more than necessary to complete a process
- Over-processing – due to poor tool or product design
- Defects – the effort involved in inspecting for or fixing defects
- Lean seeks to improve the flow (smoothness) of work by production levelling:
- UK car manufacturers used to forecast demand, make to stock, sell what was in stock and then deliver as best they could
- By contrast, Toyota total up their actual demand, turn their output volume controls to suit, meet all the variety demanded and deliver fast
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However, Lean practitioners tend to focus on cutting specific task times and costs – and that could even increase overall costs – if many of those tasks are unnecessary for the customer, cutting their costs by 10% say would make little sense
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Hence, always focus on why and how you do things for customers, and the Order Cycle Time (OCT) – big cost reductions tend to follow when you improve things for customers first