Why not store files on the desktop?

I just read the article An Irrational Fear of Files on the Desktop, where the author James Hague argues that a desktop is a fine place to store files: it is part of the filesystem, after all, and your files are "in-your-face." Those are good points.

My mom sometimes forgets where she saved her files. That's another good reason for newbies to store files on the desktop. Windows makes the Desktop appear as the root node in the filesystem graph -- at least when browsing using Windows Explorer. (Click "Up" enough in the File Open or File Save dialog, and you end up at the Desktop.) I haven't decided whether I agree with that decision.

So why not store files on the desktop? (To clarify, this is a discussion about how to guide casual computer users, not experts.)

Corporate IT tends to not synchronize desktops between computers, whereas My Documents tends to be synchronized / shared. For example, at Rockwell Collins, when I log into a new-to-me computer using my enterprise credentials, the desktop is impersonal and is locally-generated. It has some program shortcuts, but none of my personal files or shortcuts. My Documents, on the other hand, points to the network-attached-storage with all my files. This also means that if the computer's hard drive dies overnight, desktop files are gone forever.

At first I thought it's a shortcoming of Rockwell Collins' IT. After all, Windows allows synchronizing the desktop just like My Documents. But then, like with many things, experience revealed the reason. As the IT administrator for a local private school, I thought I would do things "right" and synchronize the desktop for teachers between computers. It worked beautifully, from the technical perspective. I sat back and felt proud of myself. Then complaints started rolling in.

What I didn't think about is that most programs by default make a shortcut to themselves on the desktop. These program shortcuts are synchronized across computers just like files; Windows makes no distinction. (Why not? The Great Raymond Chen explains.)

Is the problem clear now? Say the IT administrator helpfully synchronizes the desktop. When a user logs in to a new-to-him computer, he sees the desktop shortcuts to all the programs he installed to his other computer. He tries to launch them.... what, Windows cannot find the program? What the hell? The computer's broken!

It is difficult for a casual computer user to understand that just because the shortcut is there, the program isn't. That requires a surprisingly sophisticated understanding of the filesystem and the independence of the desktop from Program Files.

In the case of my private school, after getting enough complaints and having to explain over and over again, I turned off the policy that synchronizes the desktop. This also means that if a computer user stores a personal file on the desktop, it stays local. Only the user's My Documents are visible on another computer. This setup detracts from the "seamless" cross-computer experience I was hoping to achieve, but this is much easier for a casual computer user to understand.

The root cause of the problem seems to be that software installers seem to treat the Desktop as not a place for personal file storage but as a list of installed programs. No installer has ever offered to create a program shortcut in My Documents, but every installer wants to create a shortcut on the Desktop, Start Menu, and/or Quick Launch. (That's also the reason not to synchronize the Start Menu between computers.) In other words, semantically it's understood that My Documents is for the user's personal files. The desktop is semantically for anything and everything.

Is this really a good enough reason to avoid storing files on the desktop in general? After all, home users don't need to worry about corporate IT synchronization policy. Well, it's a matter of habit. Users will do what they're used to. If a user is used to the desktop being the dumping ground for all files, he'll do the same on his corporate desktop.

And that's why it can be better to store personal files only in My Documents.