GamePro - Analysis: Digital Rights Management in PC gaming.
It's not clear, however, that copy protection ever effectively deterred software criminals. When illegal distribution first became a serious issue during the 1980s, PC software developers like Infocom and Sierra attempted to maintain control of their products by bundling games with gratuitous goodies that doubled as DRM. Players were usually required to consult a game's manual for fictional codes or recipes in order to play; The Secret of Monkey Island included an infamous "Dial-A-Pirate" spinning toy that doubled as a copy protection code wheel.

Digital Trends - Microsoft Should Never Have Built the Xbox.
Let’s talk about opportunity cost, which is the cost of not doing something. Let’s go back to Microsoft’s initial choice, which was to develop a separate game platform for a market selling in the low millions with small margins and royalties, or improve the game experience in a platform selling in the hundreds millions at huge margins. That was the decision that had to be made, and by building the Xbox, Windows gaming became less strategic. PRJ’s arguments one through four are valid, but only because Microsoft made this deliberate shift. Had they put the same effort into Windows gaming and targeted the same result, the company could have used a variety of tools from hardware certification to virtual machines to provide a similar experience on gaming PCs. The consumer segment of the PC market is around 75 million users, and Microsoft has around 90% market share. However, most of the other 10% is owned by Apple and this longtime rival owns nearly 90% of the premium market.