A couple days ago in [Joel on Software][1], Joel claimed that in order for it to make economic sense to develop a Macintosh product, you had to be able to sell *25 times as many* copies as you would a Windows product.
**Bullshit.**
First of all, you can’t just assume that the relative market sizes between the Macintosh and Windows are accurately represented by their market shares. This is partly because market share is a measurement of new computer sales rather than installed base, and partly because there are broad swaths of each market that *aren’t* in the market for your application.
Secondly, it presumes that it costs the same to develop and bring to market a Macintosh product as it does to develop a Windows product. It doesn’t. It costs substantially less. The development tools on Mac OS X are the best on any platform, and speed development significantly; very small teams can create high-end applications in very short timeframes. There is a far smaller test matrix when you’re dealing with Macintosh software, and within that matrix there are far fewer bizarre interactions. There is significantly less competition in the Macintosh market, so you don’t have to spend as much on marketing and promotion of your product. Consumers also don’t have to wade through nearly as much complete garbage to discover the good applications.
Finally, you have to consider post-sales support. The support load presented by Macintosh software is also far lower than for the typical Windows product. This means lower post-sales costs, which means you get to keep more of the revenue generated by the product.
All this adds up to an excellent ROI story for Mac OS X development. You may still have the potential for a higher return on a Windows product, but you’ll also have substantially higher costs, a longer development timeline, and correspondingly greater project risk. All sides need to be weighed before deciding whether it’s worth pursuing one platform or another – you can’t just do a couple bogus back-of-the envelope calculations and decide you need to sell 25 times as many units to make Macintosh development worthwhile.
[1]: http://www.joelonsoftware.com/news/20020910.html