Commoditize Your Complements

I wrote about a post written by Joel Spolsky last year, and one of the many positive externalities positive spillovers of writing on this blog has been the fact that I’ve gotten to know about Joel and his writing. It is a positive treasure trove, and well worth dipping into.

But the reason I’m writing about him today is because I originally meant to write a post on a recent Ben Thompson post (AI and the Big Five). While going over that article and taking notes, I came across a reference to an old article written by Joel:

Once again: demand for a product increases when the price of its complements decreases. In general, a company’s strategic interest is going to be to get the price of their complements as low as possible. The lowest theoretically sustainable price would be the “commodity price” — the price that arises when you have a bunch of competitors offering indistinguishable goods. So, smart companies try to commoditize their products’ complements. If you can do this, demand for your product will increase and you will be able to charge more and make more.

I found parts of the write-up mysterious, because I’m not familiar with both the firms and the products that have been spoken about in it. Partly a function of I not knowing enough about the tech world, and partly a function of the article itself being quite old (Transmeta, Ximian, Gnome are examples, of you are wondering).

But the core insight from the article? Both spot on, and an excellent example of a TMKK in a into class about micro.

What is the core insight? A simple, almost throwaway line in micro classes:

All other things constant, the demand for a product will go up when the price of the complement goes down

And we’ve all gone through examples of how “the demand for tea will go up when the price of sugar comes down”. But consider this instead:

When IBM designed the PC architecture, they used off-the-shelf parts instead of custom parts, and they carefully documented the interfaces between the parts in the (revolutionary) IBM-PC Technical Reference Manual. Why? So that other manufacturers could join the party. As long as you match the interface, you can be used in PCs. IBM’s goal was to commoditize the add-in market, which is a complement of the PC market, and they did this quite successfully. Within a short time scrillions of companies sprung up offering memory cards, hard drives, graphics cards, printers, etc. Cheap add-ins meant more demand for PCs.

Why did this matter to Microsoft? That is, why would they want to ensure cheap add-ins (complements) for PC’s, so that the demand for PC’s (the product) go up? They didn’t actually manufacture the PC’s back then, so how were they profiting?

Microsoft’s goal was to commoditize the PC market. Very soon the PC itself was basically a commodity, with ever decreasing prices, consistently increasing power, and fierce margins that make it extremely hard to make a profit. The low prices, of course, increase demand. Increased demand for PCs meant increased demand for their complement, MS-DOS. All else being equal, the greater the demand for a product, the more money it makes for you. And that’s why Bill Gates can buy Sweden and you can’t.

As always, do read the rest of Joel’s write-up, please.


  1. What examples can you think of where this lesson has been applied in a modern context? Software or otherwise.
  2. How can those of us in the education sector think about the applicability of this lesson?
  3. Industrial organization remains an underrated subject. Discuss.