I have been a Microsoft defender for decades. “No, MS-DOS 4.0 isn’t really that bad,” I pleaded to friends almost 25 years ago. “Give Windows 98 a chance” I begged ten or 11 years later. Heck, I extolled the virtues of Vista (which I did believe in, by the way) to anyone willing to listen. But in the wake of last week’s introduction of the Consumer Preview edition of Windows 8, I can say only this: Microsoft, you’re on your own.

Never — and I’m going to repeat this for additional emphasis, never — have I been as horrified by one of the company’s products as I am by this one. (Yes, I used Microsoft Bob.) Every choice seems to have been made for a sketchy reason, and the full collection of them bears the haphazard feel of the morning after a particularly raucous college party. Scratch that: Even at my most inebriated, I’m pretty sure I would never conceive of something like Windows 8.

Don’t say I haven’t given it a chance. I have. I first used it last year, when the Developer Preview was unveiled. I was less than impressed at that point, but I assumed that Microsoft would get with the game and fix the most brazen mistakes, undo (or at least downplay) some of the more questionable “improvements,” and not dare to put it before the public again until it was in presentable shape. How wrong I was. This incarnation of Windows 8 is, if anything, even worse than the previous one — because it suggests this is what Microsoft actually intends to release.

Based on its current form, Windows 8 represents an unconscionable, and barely comprehensible, rejection of the values Microsoft has spent the last 26 years perfecting in its visual operating system. It doesn’t make computers easier to navigate and understand, it makes them more difficult, paradoxically by making the interface so brain-dead simple that it can’t do anything someone with a brain might actually want. Want to close an application without using Alt-F4? Forget it. Want the menus and settings intelligently organized? No chance. Want to just display two windows on the screen at the same time? Good luck with that.

Yes, Microsoft has released a product it’s calling Windows that doesn’t use windows as part of its primary interface. Can you figure that out? I can’t. (My colleague Sebastian Anthony claims he’s worked it out.)

Okay, correction. I can figure it out, and it’s related to the only good reason for Windows 8’s existence: its tablet friendliness. Microsoft has obviously reached the same conclusion as Apple, Google, and many technophiles and decided that tablets and phones are where most computing will be done in the future. And the new Metro interface, which displaces the Desktop as the initial Windows 8 environment, makes sense when looked at that way. Plenty of extra-large icons and buttons, a heavy focus on horizontal scrolling, and using the whole screen for every task — this is all commonplace tablet stuff.

But what Microsoft forgot, or perhaps ignored, is that the world is not yet all tablets. There are millions upon millions of current or prospective desktop and laptop owners out there who want and need to use their computer with their mouse rather than their finger, and think being able to flip instantly between applications — and see them simultaneously — isn’t a feature but a necessity. And, of course, there are plenty of serious users who don’t want the PC on which they spend huge chunks of their waking life to look like it was designed by Fisher-Price. They want their interface and their way of working to be completely under their control. Which, until now, it always has been.

With Windows 8, Microsoft is taking most of your choices away. Once you open programs, you don’t get to decide to close them. You don’t get to decide if you’d like a nonintrusive log-on screen. You don’t get to decide if you don’t like Metro enough to boot into it. You don’t get to decide how, or even if, you want to arrange programs on your screen. Microsoft will do it all for you, because that’s how tablets work — and your computer not being a tablet is irrelevant. One imagines that Microsoft sees the industry as one day not letting you decide whether your computer even is a tablet. Quite probably that’s where we’re headed. But we’re not there yet.

Next page: You have one last chance, Microsoft; please don’t blow it