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'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%. It's likely to remain so, notwithstanding Dell's move to offer pre-installed Ubuntu on a bunch of PCs and laptops. That's the biggest boost desktop Linux has ever received, but it's too little, too late.

One caveat: While I believe all the arguments I lay out below are valid, I don't assert them with the faith-based certainty I see from many Linux supporters about their claims. This article is presented as an entrée to a healthy debate. If you don't agree with me, please leave a comment below, or e-mail me directly at awolfe@cmp.com.

Before I dive into the seven reasons Linux on the desktop will remain an also-ran, let's frame the debate with a quick analysis of the current market share of the open-source operating system.

Pitiful Market Share

Let's face it, in the minds of most professionals, when you're talking Linux, you're talking server. As the oft-cited and sometimes accurate Wikipedia points out: "Historically, Linux has mainly been used as a server operating system, and has risen to prominence in that area; Netcraft reported in September 2006 that eight of the 10 most reliable Internet hosting companies run Linux on their Web servers."

However, when one delves deeper, the data show that Linux is only doing respectably in servers. It isn't eating Microsoft's dust, though one might expect that it would be, since all evidence indicates that Web site admins prefer Linux Apache to IIS on Windows.

According to Gartner's latest figures, 67.1% of servers shipping during the second quarter of 2007 were fitted with a Microsoft OS; 22.8% had Linux. Interestingly, that was down slightly from the 23.1% share Linux had in the year-earlier period.

Okay, so server Linux is solid, regardless of how you parse the figures. Whither its desktop cousin? There, expectations and perceptions seem to trump reality.

According to the W3Counter Web stat site, Linux recently achieved a 1.37% share to inch past Windows 98 (Windows 98!). As Ars Technica pointed out, in reporting this news:

"This is a somewhat empty victory for Linux enthusiasts, who have been predicting the imminent arrival of the mythical 'year of the Linux desktop' for as long as I've been a Linux user. Linux's 1.34% market share falls far short of the rosy 2008 estimates made by Siemens in 2003."