Continuous Improvement
The improvement cycle
Continuous improvement is incremental, ongoing, and everyone's job. PDCA/PDSA - Plan (define the problem, baseline data, root cause, countermeasure), Do (pilot the change), Check/Study (compare results to prediction), Act (standardize or adjust) - is the backbone. Skipping Plan or Act is the most common failure: teams jump to solutions or never lock in gains.
Major approaches
- Kaizen: small, frequent, low-cost improvements by the people doing the work; relies on standard work and suggestion systems.
- Lean: remove waste - overproduction, waiting, transport, overprocessing, inventory, motion, defects (plus unused talent) - and improve flow and pull.
- Six Sigma: reduce variation; DMAIC (Define, Measure, Analyze, Improve, Control) for existing processes, DMADV for design.
- Benchmarking: compare against best practice to set targets; it is learning, not copying.
- Corrective action removes the cause of a detected nonconformity; preventive action addresses a potential one.
Traps
Questions reverse DMAIC order, call benchmarking a one-time comparison, or label an inspection finding a root cause. "Operator error" is a symptom, not a cause - keep asking why until a system cause appears.
Worked example
A team is late on 30% of orders. Plan: stratify late orders by shift and product, and find that one product's changeover pushes orders past cut-off. Do: pilot a sequenced schedule for two weeks. Check: lateness falls to 9%. Act: update the scheduling standard and train the planners. Only then is the gain durable.