Why Japanese companies do so many different things

Photos from Lars Tunbjörk’s “Office” seriesConsider Toto.If you spend much time in American public bathrooms, or rather if you’re simply a particularly attentive patron of American public bathrooms, you’ll probably have noticed Toto’s toilets at some point or another: they’re distinguished by a quite memorable serif-font “TOTO” logo. Toto toilets aren’t quite dominant in American bathrooms, since they have healthy competition from our homegrown toilet champions American Standard and Kohler—though Toto is doing better and better as Americans start to fall in love with the bidet-toilet—but globally Toto is the world’s largest manufacturer of toilets and bidets. And in its home country of Japan, Toto is simply everywhere: 80 percent of Japanese homes contain a Toto bidet-toilet.And if you’re a longtime Toto shareholder—maybe an investor with a particular interest in bathroom fixtures—this has been a wonderfully lucrative year for you. Toto’s stock is up 60 percent year to date; in just the last few weeks, it’s risen by 30 percent. Toto is doing better than ever: its net profit, in the first quarter of 2026, was up 230 percent year over year.But Toto’s remarkable year doesn’t have much to do with toilets or bidets. Toto might have been founded in the 1910s to “provide a healthy and civilized way of life” through affordable toilets, and in the decades since might have become the global leader in the bathroom game. But Toto also does a lot of other things. Toto manufactures not just bidets and toilets but also bathroom tiles, prefabricated bathroom modules, faucets, modular kitchens, photocatalytic coatings for buildings, and assistive equipment for the elderly. And, most importantly, Toto has a very lucrative sideline in the fabrication of memory chips.Since 1988, in a once-obscure corner of the company called the “advanced ceramics division,” Toto has been producing a very particular component called the electrostatic chuck, or the “e-chuck.” The e-chuck is a sort of high-precision ceramic plate, about the size of a steering wheel, that uses electrostatic force to hold a silicon wafer perfectly flat and thermally stable while memory chips are etched into it with bombardments of plasma.

Making these components is extraordinarily difficult, since the ceramic body needs to have near-zero particle generation and be polished to submicron flatness: and this means that there are only a few companies in the world that are capable of manufacturing e-chucks reliably. Almost all of them—Shinko Electric, NGK, Toto, Kyocera, Sumitomo Osaka Cement, Niterra—are based in Japan.For most of its history, the advanced ceramics division was a rounding error on Toto’s balance sheet: the money maker, as it had been since the 1910s, was the toilet and bidet business. But we’re in a new era. Demand for AI is exploding, meaning that demand for the high-bandwidth memory that AI data centers require is exploding, meaning that demand for memory chips is exploding, meaning that demand for e-chucks is exploding. And so Toto’s advanced ceramics division is suddenly the company’s largest business, generating the majority of its operating profit. Toto’s leadership, suddenly awash in AI-driven revenue, announced that they would double down by investing hundreds of millions in expanded electrostatic chuck production: the toilet company had become, quite unexpectedly, a supplier to the semiconductor supply chain. The Toto story is a fun and interesting illustration of corporate diversification and how strange bets can pay off. But that type of diversification—a toilet company that also produces photocatalytic coating and high-precision components for semiconductors—isn’t really unique to Toto. Practically every company in Japan seems to do a thousand very different things.Consider, for example, Kyocera, another one of the e-chuck makers. Kyocera was founded in 1959 as a producer of ceramic insulators for cathode-ray tubes; today it manufactures not only industrial ceramics but also printers, smartphones, ballpoint pens, kitchen knives, solar PV modules, lens components, industrial cutting tools, automotive camera modules, electronics components, semiconductor packaging, biocompatible tooth and joint replacements, UV-LED curing systems, LCD systems, medical products, and lab-grown gemstones. Or another e-chuck maker. Sumitomo Osaka Cement, as you might have been able to deduce from the name, produces cement and ready-mixed concrete; but it also produces optical components, measuring instruments, industrial ceramics, artificial marine reefs, cosmetics and nanoparticle materials.

And this degree of diversification extends to many of Japan’s most famous companies. Yamaha, for example, manufactures pianos, motorcycles, guitars, drums, boats, snowmobiles, ATVs, audio equipment, golf clubs, tennis rackets, home appliances, specialty metals, molding and bonding equipment for semiconductors, and industrial robots. Hitachi makes nuclear reactors, power grids, railway systems, elevators, semiconductor manufacturing equipment, medical imaging devices, data storage, IT consulting, and industrial machinery. Even a company as simple as Oji, Japan’s largest paper company, has been drawn into the production of disposable diapers, functional films, adhesives, cellulose nanofibers, and wood-based EUV photoresists; and it also operates a hotel, an airport catering business, a concert hall, and an insurance agency.All of which is to say: Japanese companies do a lot of things.There are, of course, other countries with companies that “do lots of things”: much of Indian economic life, for example, is defined by the sprawling activities of a few large business clans—the Adanis, the Ambanis, the Tatas, the Birlas. But India is a relatively poor country with a low level of economic specialization, and the sprawling conglomerates that dominate its economy focus on relatively simple things like cement, steel, ports, and telecommunications. Japan, by contrast, is a wealthy, developed society—by one measure, the most economically complex country in the world. What’s striking about Japanese companies is not that they do lots of different things but rather that they do them very well. There are all sorts of high-precision inputs—the e-chuck being just one example—that are produced virtually only by Japanese firms.This is very different from how most wealthy countries operate. American firms, for example, tend to prioritize focus above all else: it would be bizarre for an American paper mill to also operate a concert hall and an airport catering business, or for American Standard or Kohler to somehow have something to do with semiconductors. Even a country like Germany, which matches Japan in its depth of high-precision firms, has nothing like Japan’s corporate diversification. Only a few large conglomerates, like Siemens, have anything approaching the lateral breadth of the Japanese firm.

South Korea—whose economic system was not coincidentally modeled off the Japanese one—does have a few chaebol conglomerates, like Samsung and SK, that truly do as many things as Japanese companies. But these are economy-dominating, state-entangled megafirms, cultivated as national champions by Korean industrial policy. They look nothing like, say, Sumitomo Osaka Cement, which is hugely diversified despite being relatively small. (“Look what they need to mimic a fraction of our power!”)So why are Japanese companies like this? Why do they do so many different things? And how do they manage to do so all those different things so well?Here is the answer I want to suggest: Japanese companies excel in lots of very different domains because it’s inherent in how they’re structured. The form of the corporation that we know and love in the United States—specialized, market-oriented, governed by shareholders—is just one form that the corporation can take; but it’s not the only way to coordinate capital and labor in a successful and profitable way. The protean corporations of Japan are best understood as a different species of thing altogether: better at some things, worse at others, but still highly adapted to their particular environment. And the things that they’re very good at turn out to be extraordinarily helpful for all sorts of things in which American companies tend to struggle.To see why, we need to learn a little bit about the economics of industrial organization.In 1990, two economists—Paul Milgrom and John Roberts, both of Stanford—published a paper called “The Economics of Modern Manufacturing.” You should forgive them for the rather bland title. It was a very interesting, and very influential, paper.Milgrom and Roberts started out by noting that manufacturing was “undergoing a revolution.” One paradigm of production was getting swapped out for another. In the past, there had been the “Fordist” paradigm: the factories that worked in this paradigm had long assembly lines of standardized goods, large buffer inventories, narrow and repetitive jobs for their workers, and dedicated single-purpose machinery. But that approach was being superseded by a new model: “a vision of a flexible multiproduct firm that emphasizes quality and speedy response to market conditions while utilizing technologically advanced equipment and new forms of organization.” This was the “post-Fordist” vision.

In practice, this meant shorter production runs, rapid changeovers between products, smaller and more frequent deliveries from suppliers, workers trained to operate multiple machines and diagnose problems on the fly, and quality control embedded at every stage of the process. It was an entirely different way of producing things.The question that Milgrom and Roberts wanted to answer was simple: why did all of these changes come as a package?Maybe it made sense for a specific firm to adopt shorter production runs; but why did it also make sense for them to do everything else in the “post-Fordist” category? Why did the changes seem to be so tightly clustered, with firms either having none of these practices or having all of them?The explanation that Milgrom and Roberts offered was that the practices were complementary. Adopting any one of the “post-Fordist” practices raised the returns to adopting others, such that adopting only one of the practices didn’t make nearly as much sense as adopting the entire set.Milgrom and Roberts formalized their argument using the mathematics of supermodular functions. But you don’t really need to know anything about math to understand the idea intuitively.Here’s an illustration. Let’s say you run a factory. You decide that you want your lines to produce fewer defective goods: maybe you want to improve your yield from 95 percent to 98 percent. So you decide to invest in better training for your workers: maybe training now lasts six weeks instead of two weeks. This works, and now your yield is higher; but that change makes other things more attractive too. For example: now that your yield is higher, it makes sense for you to reduce your inventory, since fewer defects mean you no longer need a large buffer of spare parts to replace the bad ones. So now you’ve cut your inventory: but now it makes sense for you to shorten your production runs and switch more frequently between products, since without a mountain of inventory to work through you can afford to change what the line is making. And if you’re switching frequently between products, then it makes sense for you to invest in flexible, reprogrammable machinery instead of dedicated, single-purpose equipment. So one relatively small tweak shifts the entire calculus of what you do.In short: each practice makes the others more valuable, and each practice is valuable because it’s implemented alongside other complementary practices.