Signs of Change in Japan's Strict Demand for Precision: A Supply Chain Beginning to Open

Demanding specifications are one of the wellsprings of the quality Japan is known for around the world. An uncompromising attention to detail has built products that customers trust. Yet that rigor carries an overlooked pitfall: the failure to separate what is necessary from what is merely sufficient. On the factory floor, the precision a part genuinely requires and the extra margin added "just in case" are too often run together as if they were the same thing.

I learned this firsthand, supplying precision mounting components. The drawing stated a tolerance. Yet there was an unspoken assumption on the floor that the part would, of course, come in at roughly half that value. It was never put to me as a request. It was simply treated as how things ought to be.

Why half? No clear functional reason was ever given. Japanese manufacturing has a deep-rooted habit of stacking on customary safety margins, over and above simply meeting the drawing. The problem was not the strictness itself. It was that the number had been severed from the reason for it. A tolerance should be derived backward from the function a part must perform. But an assumption that "half is only natural" — never even voiced as a requirement — leaves no opening to ask why that value is the right one.

This is not my experience alone. In a survey by Nikkei Monozukuri, nearly 80% of respondents said they felt customer quality requirements were excessive.¹ Over-quality drives up cost and wears down maker and buyer alike. Behind it lies a homogeneous competition in a domestic market of exacting customers — a structure in which there is little brake on going too far.² Tellingly, the same floor also holds a quiet counter-view: that as long as a part mates with its mating component and there is no functional problem, it need not strictly meet the drawing's tolerance.³ The gap between numbers and function was a contradiction the industry itself half-recognized.

For overseas manufacturers, this invisible markup has been the barrier to entering the Japanese supply chain. Halve a tolerance and the required equipment, the inspection burden, and the defect rate all climb. Cost swells with no relation to function, and the basis for it stays opaque. The quality is impeccable, but the wall of requirements is high and the cost is hard to predict — a sentiment many procurement managers will recognize.

But the tide is turning. A concept called tekishitsu-tekika — "right quality, right price" — is spreading across Japanese manufacturing: identify the quality level the market truly demands (the right quality), and pay the fair price that makes it sustainable to deliver (the right price). Rather than vaguely chasing "high quality," buyer and supplier hold a dialogue and design sustainable quality together. Against a backdrop of labor shortages and reflection on quality scandals, this thinking is steadily gaining support.⁴

One early example points the way. Takahiro Takemura, a former Denso engineer, rethought specifications from the ground up on functional grounds when entering emerging markets. By his account, because Denso held even the variation of raw materials to extreme tightness, the price of parts meeting those demands could easily run 1.5 to 2 times higher. He identified that excess margin, pared it away, and achieved roughly a 40% cost reduction.⁵ The key point is that he did not lower quality. He pinned down the function that mattered and removed only the margin that did not bear on it — a return to honest specifications, where drawing, actual practice, and function agree.

This shift does not erode the essence of Japanese quality. If anything, the reverse. The excess margin that once made entry daunting is falling away, and necessary and sufficient are finally being sorted out. An era is approaching in which one can access Japanese manufacturing with the right requirements, at the right cost.

Japan's precision remains the best in the world. What has changed is that this precision is, at last, becoming available at a fair price. Today, the door to the Japanese supply chain is more open than it has ever been.

References

1. "Excessive demands that create no value erode quality," Nikkei xTECH, 2021 (Japanese-language source) — https://xtech.nikkei.com/atcl/nxt/column/18/01707/00003/

2. "Over-quality," Kobe University MBA (Japanese-language source) — https://mba.kobe-u.ac.jp/business_keyword/7916/

3. "Resource shortages, tight deadlines, and over-quality as an escape hatch," Nikkei xTECH, 2021 (Japanese-language source) — https://xtech.nikkei.com/atcl/nxt/column/18/01707/00007/

4. "Behind quality fraud, the 'mature product': can management make the bold call?," Nikkei xTECH, 2021 (Japanese-language source) — https://xtech.nikkei.com/atcl/nxt/column/18/00138/080300853/

5. "The over-quality that perfectionism invites," Nikkei xTECH, 2021 (interview with Takahiro Takemura; Japanese-language source) — https://xtech.nikkei.com/atcl/nxt/column/18/00134/062100264/