Why HD-DVD and Blu-ray are dead on arrival.

Until recently, the history of home entertainment was the history of encoding formats. For movies and music to get into our homes, manufacturers had to invent some medium that was capable of holding Star Wars or ABBA Gold. And so it went: vinyl, eight-track, cassette, Betamax, VHS, CD, DVD. Our shelves filled with slabs of plastic, spools of magnetic tape inside cartridges, and 5-inch discs stamped with binary-encoded metal foil.

Now, home entertainment has a new idea: high-definition video. By increasing the number of pixels in an image, HD encoding can deliver a sharper picture. Because high-definition images pack more visual data, HD movies require more storage space than DVDs can provide. So, naturally, we've now got two new encoding formats: the Toshiba-backed HD-DVD and Sony's Blu-ray.

The movie studios and electronics manufacturers think—wrongly—these new high-def formats will extend the market for home-entertainment media indefinitely. Both formats will fail, not because consumers are wary of a format war in which they could back the losing team, a la Betamax. Universal players that support both flavors of HD should appear early next year. No, the new formats are doomed because shiny little discs will soon be history. Here are four reasons why.