Rob Pike gave a presentation in 2001 entitled “The Good, the Bad, and the Ugly: The Unix Legacy.” His main point is that diversity has been bad for Unix. He opens his presentation with a couple of quotes to set this up.
‘‘The number of UNIX installations has grown to 10, with more expected.’’ — The UNIX Programmer’s Manual, 2nd Edition, June, 1972.
The number of UNIX variants has grown to dozens, with more expected.
He discusses much more than diversity, and I believe the more interesting parts of his talk are on other topics, but he begins and ends with diversity. One of his last slides says
Microsoft succeeds not because it’s good, but because there’s only one of them. … Unixes of the World, Unite!
Joel Spolsky has a different take on the differences between the operating systems in his article Biculturalism. Spolsky says that Unix software is programmer-friendly but Windows software is user-friendly for the vast majority of users who are not programmers. But Spolsky does touch on the diversity issue that Pike raised.
For example, Unix has a value of separating policy from mechanism which, historically, came from the designers of X. This directly led to a schism in user interfaces; nobody has ever quite been able to agree on all the details of how the desktop UI should work, and they think this is OK, because their culture values this diversity, but for Aunt Marge it is very much not OK to have to use a different UI to cut and paste in one program than she uses in another.
Just to throw in my two cents worth, I’ll mention my blog post Where the Unix philosophy breaks down. The Unix philosophy is to write little programs that do one thing well, then sew these little programs together to do your work. The problem is that many people lack the desire or skill to do the sewing. They want to avoid the transaction costs of switching software applications. Pike alludes to this problem, dismissively saying that people want “hand-holding” rather than pipes.
I don’t think this desire for integrated applications is necessarily a problem for Unix, only for the Unix philosophy that Unix doesn’t follow too strictly. The emphasis on orthogonal programs is a laudable ideal. It just needs to be tempered a bit for the convenience of mortal users.