Ballmer on monoculture
anon April 07 2004

[...]

QUESTION: .. isn't the preponderance of one major operating system part
of the problem?
STEVE BALLMER: No.

[...]

... you know, Linux gets attacked all the time. The Mac, less so, because
the Mac's an even more narrow percentage of the population ..

http://blog.seattlepi.nwsource.com/microsoft/archives/002561.html