Waving the free market flag and complaining about MS in the same comment is contradictory. Sure, I'll concede that MS products aren't the best products out there, but customers decide what has the most value. Here are some of the ways that MSFT products, while possibly technically inferior, created value:
-hardware didn't matter. DOS/Windows would run on any (sufficiently powerful) PC
-everyone had it, so it was already familiar (people value consistency)
-MSFT on a PC has always been cheaper than a Mac, and people valued the stuff they could buy with the difference more than they valued the qualities of a Mac
-there has always been more software for Windows. This matters less now because of virtualization and the internet, but this was a big deal in the 80s and 90s.
-the money they spent on marketing and bizdev made their products easier to buy
-hardware didn't matter. DOS/Windows would run on any (sufficiently powerful) PC
-everyone had it, so it was already familiar (people value consistency)
-MSFT on a PC has always been cheaper than a Mac, and people valued the stuff they could buy with the difference more than they valued the qualities of a Mac
-there has always been more software for Windows. This matters less now because of virtualization and the internet, but this was a big deal in the 80s and 90s.
-the money they spent on marketing and bizdev made their products easier to buy
Basically, they did this: http://www.joelonsoftware.com/articles/fog0000000052.html