Lean means less waste, not more robots
Lean is the steady removal of waste (muda), uneven work (mura) and overburden (muri). It rests on flow, pull, quality built in at each step, and respect for people. A factory can be fast and cheap and still not be lean.
Toyota’s word for its machines is jidōka, automation with a human touch (自働化): a machine that stops and flags a problem so a person can fix the cause. Plain automation (自動化) is also read jidōka. The only difference is that Toyota’s version adds the radical for “person.”
Toyota uses robots but keeps people close to the work
At one Zeekr plant, robots outnumber people 10 to 1, according to a UK car site that toured it. In 2014 Toyota went the other way in some jobs. It put people back where robots had worked, so they could learn the work and improve it.
A plant with no people can lock waste in place, with nobody left to see it.
China develops a new car in half the time
Chinese programs take 15 to 24 months from concept to launch. Japanese makers take about 48. Tōyō Keizai, a Japanese business weekly, publishes the comparison, and Toyota’s president calls China the fastest-evolving region.
Source: Tōyō Keizai; Toyota statements via InsideEVs.
Chinese cars are also leaner in design. A Nikkei teardown of the BYD Seal found an 8-in-1 power unit and few control units. Fewer parts means fewer joints and fewer handoffs. That waste is removed from the car, not from the factory.
Tesla Shanghai is level with Toyota Georgetown per worker
Tesla’s Shanghai plant built about 947,000 cars with about 20,000 workers, one car every 37 seconds. Toyota’s Georgetown, Kentucky, plant built about 550,000 vehicles and 600,000 engines with about 10,000 people. Shanghai is also an American company’s plant. BYD’s own line-speed and automation figures come from the company and do not agree with each other.
Calculated from autoevolution (Shanghai) and Toyota (Georgetown) figures. Georgetown also builds engines.
BYD holds 2.6 times as much inventory as Toyota
Lean was built to cut inventory. BYD held 110.7 days of it in March 2026, and the figure was rising. Toyota holds about 42 days.
Source: GuruFocus, from company filings; Toyota FY2025 results.
BYD’s cost edge comes from integration, not productivity
Rhodium Group broke down BYD’s cost edge of about $4,700 per car. Most of it comes from making its own parts and from cheaper engineers. Rhodium found no evidence that BYD’s workers are more productive.
Source: Rhodium Group, February 2026. The four parts add up to about $4,600.
Labor costs about $585 per car in China and $769 in Japan, according to Oliver Wyman’s Harbour team. The gap comes from lower wages and cheaper designs, not from fewer hours per car.
Chinese cars now match on early quality, not on durability
In J.D. Power’s 2026 China study, domestic brands beat international brands on early quality for the first time. A year earlier, the same survey found early quality across the industry falling as launches sped up.
Durability still favors Toyota. Lexus topped J.D. Power’s 2025 US dependability study.
Source: J.D. Power China, 2025 Vehicle Dependability Study.
Unsold new cars come back as used cars
Overproduction is the waste Toyota was built to refuse. In China, makers and dealers register new cars and sell them as zero-mileage used cars (0公里二手车, líng gōnglǐ èrshǒuchē). Geely’s chairman criticized the practice in public. CNBC reported that Zeekr and Neta inflated sales through an insurance scheme.
Suppliers and workers carry the cost
BYD pays many suppliers with Di-chain notes (迪链, Dílián). Suppliers say real payment takes 8 to 10 months. The inventory and its cost move onto their books. China now requires payment within 60 days.
China Labor Watch found BYD’s assembly relies on low-paid workers and high turnover. In 2026 the European Parliament began examining labor practices at BYD’s plant in Hungary.
Toyota wins five of eight measures
PP100 means problems per 100 cars. Not measured means this guide found no comparable figure.
China wins development speed and product design. Early quality is close to even. Toyota leads on the rest. The productivity verdict rests on the absence of any Chinese edge in the data, not on a direct hours-per-car study.
BYD’s founder still aims at Toyota
Wang Chuanfu, who founded BYD, has said: “BYD’s goal is to be the future Toyota” (比亚迪要做未来的丰田, Bǐyàdí yào zuò wèilái de Fēngtián).
Toyota is learning from China in return. Its executives said they were “flabbergasted” by BYD’s development speed. Its joint venture with GAC now makes new-car decisions in China.
Nobody has measured these plants from the inside
No published study compares hours per car in Chinese EV plants and Toyota’s. No Western lean expert has published a report from the floor (gemba) of a BYD, NIO or Zeekr plant. Most line-speed and automation figures come from the companies themselves.
This verdict rests on financial filings, quality surveys and industry data. Chinese plants are faster and cheaper. On flow, durability and people, the evidence so far says they are not leaner.