4. Development Hell
It never bodes well for a game becoming a series when the development is so laboured. Originally given the generic title Race'n'Chase, it was conceived as a "fast and fun multiplayer racing game". So, basically Micro Machines. Incredibly, it spent nearly a year and a half in development. Gary Penn, a developer for DMA, was quoted as saying that the game very nearly didn't happen, and explained that it was, in his own words, "awful". He continued that "it was too sim-y, unstable, and had many, many bugs". They cranked up the police AI as an experiment, and Grand Theft Auto is the game that resulted.
3. Juvenile Humour
A few months ago, Tomb Raider II came out - a sequel well earned because the original was an intelligent, labrinthine, and beautiful looking 3D puzzler. Grand Theft Auto has a fart button. It's not incidental, random or context sensitive. It's a whole button on your PlayStation controller, specifically mapped for farting. 10 year old boys might find it funny, but this game is rated 18. This kind of jarring contrast will easily ensure Grand Theft Auto never finds a core audience.