Short bio: Computer Scientist, FOSS supporter (read more)
Tux Machines (TM)-specific
It is inarguably accurate to note that, while Linux is a success on the server side -- Apache on Linux runs more Web sites than Microsoft (MSFT)'s ISS, though the latter is gaining -- the open-source operating system has been a dismal failure on the desktop. There are at least seven solid reasons, which I'll detail below, why Linux hasn't moved the needle beyond a single-digit desktop market share since it hit the scene in 1991, and never will.
Desktop Linux's failure to launch is all the more mystifying when you consider that it's hard to think of any technology which has been backed by such an enthusiastic and committed group of supporters. Unfortunately, that boost has largely backfired.
Average PC users haven't been swayed by vehement protestations from Linux supporters that it's so clearly superior to anything and everything from Microsoft. It seems clear that more users have been turned away by the outright distain hurled at them from many open-source initiates, than have been moved to overwrite their Windows installs.
While Ubuntu, the newest and friendliest distro, has done much to reduce the alienation of common folks, desktop Linux remains mired at a market-share of less than 2%.