From this article at Reuters:
The new platforms are expected to offset what Florin [Gerhard Florin, Electronic Arts’ head of European publishing] sees as a disappointing early start for online gaming. The prospect of amassing a core of gamers who pay a monthly subscription to battle other global combatants on the Internet has yet to take off.
Florin attributed the slow take-up to a nagging fear that a gamer could be humiliated in challenging an unknown foe.
“We expected millions of people wanting to play the online games and we have found that, no, they don’t. There is a pretty easy reason. If you play tennis and you don’t know your opponent you are careful whether you should play against him. The same is true with online. If you go online you could be slaughtered or cheated,” he said.
Overcoming the social aspect of online gaming, he added, will hold back the market in the short term.
I think this is probably the most frustrating thing in online gaming. It is almost impossible to win (other than when I am playing with a known group of friends), because those who do game online tend to be those who spend far too much time gaming online. So it isn’t that one might be humiliated, it’s that one will be humiliated. Of course, years ago I was beaten at Command and Conquer by an eight-year-old. When one throws in “unsportsmanlike behavior”—everything from player-killers to abusive language—as well as lag time and trouble keeping a connection to many servers, the appeal of single-player games is obvious.
I do like to play against human opponents. My son John is very challenging, especially at WarCraft III, but our skills are near enough that I can beat him when I really work at it. When I play with Isaac and David we either team up against computer-AI-driven opponents or give them one or more computer partners to help balance things out (except in the Jedi Knight series, where David needs no help). Overall, though, it is rare that online gaming is very fulfilling to the average gamer.