Lean production

Lean production (lean manufacturing) is a systematic method for minimising waste within a production system while maximising customer value and productivity. It derives from the Toyota Production System and was popularised by Womack, Jones and Roos in "The Machine That Changed the World" (1990). "Lean" means doing more with less: less human effort, equipment, time and space.

Principles (Womack and Jones, "Lean Thinking")

1. Specify value from the customer's view.
2. Identify the value stream and remove steps that add no value.
3. Create flow: make value-adding steps flow without interruption.
4. Establish pull: produce only on customer demand.
5. Seek perfection through continuous improvement.

Seven wastes (muda)

Tools

Value stream mapping, 5S, Kanban, JIT, Kaizen, Poka-yoke (mistake proofing), Andon, standard work, Six Sigma (Lean Six Sigma).

Customer demand -> Pull -> Flow -> Value
        ^__________ Continuous improvement

Benefits

Lower cost, shorter lead time, higher quality, better use of space and people, higher customer satisfaction.

Limits

Needs cultural change, stable demand and reliable suppliers; causes initial disruption.

Lean in software and IT projects

Lean software development eliminates waste such as unnecessary features and handoffs, delivers quickly and builds quality in. Kanban boards and work-in-progress limits apply the same ideas.

Example: An IT help desk maps its ticket process, removes duplicate approval steps and cuts the average resolution time from 3 days to 1 day.