Earlier quoted context omitted.
World of Warcraft dominates the MMORPG market. Why? they created the best damn product. Go free to get lots of broke users if you want to help scammers serve ads to those users.
WoW also offers a lot of free months to players. Sign up a friend, both of you get free months. I almost said "and WoW isn't the best damn product," but that depends on your definition of 'best.' It almost mirrors the Mac/Windows thing. Connoisseurs tend to scoff their noses, yet they just keep on selling... WoW is a mediocre product executed _perfectly_.
Define mediocre.