2.4.1 · Kaizen · Waste elimination · Unit cost chains — using Dyson, Land Rover, Cadbury & Haribo
The six pillars of lean manufacturing
Stock
Just-in-time (JIT)
Stock arrives exactly when needed — zero buffer. Eliminates holding costs. Requires highly reliable suppliers. Used by Land Rover and Dyson's supply chain.
Culture
Kaizen
Continuous improvement — every employee, every day, at every level. Small incremental improvements accumulate into major efficiency gains. Originated at Toyota; adopted by Cadbury's Bournville plant.
Layout
Cell production
Small multi-skilled teams complete a whole product or component end-to-end. Builds quality ownership and reduces defect rates. Land Rover's Solihull assembly model.
Workplace
5S methodology
Sort, Set in order, Shine, Standardise, Sustain. Eliminates wasted time searching for tools, reduces errors from poor organisation. Applied at Haribo's production facilities.
Waste
The 7 wastes (Muda)
Overproduction, waiting, transport, overprocessing, inventory, motion, defects. Lean aims to eliminate all seven. Identifying waste in a business context is a key Edexcel evaluation skill.
Quality
Andon / stop-the-line
Any worker can halt the production line if they spot a defect. Prevents defects from passing further down the process. Counterintuitive — stopping the line saves money in the long run.
Identify the waste — scenario trainer (the 7 muda)
Lean manufacturing identifies 7 types of waste (muda). For each scenario, identify which type of waste is occurring. Knowing these is essential for Edexcel evaluate questions on lean.
Scenario 1 of 6
out of 6
Unit cost consequence chains — tap a scenario to build the chain
Cadbury — kaizen
Land Rover — lean
Dyson — automation
Haribo — batch waste
Cadbury — over-utilisation
Unit cost calculator — Land Rover vs Haribo
Land Rover — Solihull
4,200 vehicles/week · £840m fixed costs/year
Haribo — Pontefract
Batch production with downtime
Total fixed costs for the period
Actual output this period
Materials + direct labour per unit
Exam practice
Analyse — 9 marks
Cadbury's Bournville factory has implemented a kaizen (continuous improvement) programme. Analyse two ways in which this could reduce Cadbury's unit cost of production.
Point 1 — Waste reduction: Kaizen encourages workers to identify and eliminate muda at every stage — overproduction, waiting time, unnecessary movement of materials. Even small savings per bar compound across billions of units annually.
Develop: If a kaizen team identifies that chocolate cools 10 seconds faster by repositioning a fan — reducing bottleneck time — the flow line runs 2% faster. At Bournville's scale, 2% more output from the same fixed costs reduces fixed cost per bar significantly.
Consequence: Lower unit cost → Cadbury can either improve gross profit margin (keep selling price constant) or reinvest margin in marketing — both strengthen its competitive position against Nestlé.
Point 2 — Quality improvement: Kaizen reduces defect rates by building quality consciousness into the production culture. Fewer defective bars means lower material and labour waste — every bar that fails quality inspection represents sunk costs.
Develop: If Bournville produces 2 million bars/day and kaizen reduces the defect rate from 0.5% to 0.1%, that's 8,000 additional sellable bars per day — significant additional revenue from the same fixed cost base.
Consequence: Higher yield from the same inputs → unit cost falls → margin improves. This is why Cadbury has consistently invested in lean programmes despite their upfront training cost.
Evaluate — 20 marks
"Introducing lean manufacturing is always the most effective way for a business to reduce its unit costs." Evaluate this view with reference to Cadbury and one other business you have studied.
KAA For — waste elimination: Lean eliminates the 7 wastes systematically. Cadbury's kaizen programme has delivered measurable efficiency gains at Bournville — reducing overproduction, defect costs and waiting time. These savings directly reduce unit cost without requiring additional capital investment.
KAA For — culture and motivation: Lean manufacturing (via cell production and kaizen) increases worker engagement — workers own quality rather than passing it to an inspector. Lower absenteeism and turnover reduces indirect labour costs. Land Rover's cell model at Solihull demonstrates that motivated teams produce fewer defects per vehicle.
Evaluation Against — capital investment may be more impactful: For Dyson, the most significant unit cost reduction came not from lean culture but from moving production to automated flow lines in Malaysia. The capital investment in robotics reduced variable cost per unit far more dramatically than any incremental kaizen improvement. Lean and capital investment are not mutually exclusive, but the question asks what is "most effective" — for capital-intensive products, automation often wins.
Evaluation Against — "always" is too absolute: Lean works best in manufacturing contexts with significant human labour in the production process. For a business where production is already fully automated, there is little human waste to eliminate. Similarly, lean requires a significant cultural investment — resistance from workers or middle management can cause programmes to fail, as seen in several UK manufacturing case studies.
Evaluation Against — other routes: Purchasing economies (bulk buying) may reduce unit costs more rapidly than lean for a confectionery firm like Haribo. Outsourcing non-core processes may eliminate unit costs entirely in some areas. Lean is one tool, not the only one.
Conclusion: Lean manufacturing is highly effective at reducing unit costs in labour-intensive manufacturing — the evidence from Cadbury and Land Rover supports this. However, "always most effective" is too strong: for heavily automated businesses, capital investment delivers larger savings; for firms where the competitive priority is innovation rather than cost, lean may deliver less value than R&D investment. The most effective approach depends on the industry, production method, and strategic position of the firm.