So many releases never see much retail exposure, and many sit on shelves for a few scant weeks before being removed to make room for new products. It's a very difficult retail environment for computer game publishers. The reason gaming is a big business is that the few real hits each year can make a lot of money. But the business operates in ways that fundamentally make no sense. Down the line, you can see a point where video games will be sold in electronic form and jettison their bodies entirely.
Doom points the way.
Doom is a fulcrum. Doom's publisher, sold more than 150,000 copies directly to consumers. Retail was the icing on the cake. But then came the CD-ROM revolution, and software bloated. Computer games went from a few megabytes to a few hundred megs of data.