A brief explanation why…
Nearly cancelled for being in such poor shape, the first Grand Theft Auto was originally intended to be a fast-paced multiplayer game of cops and robbers centered on racing. Called "Race'n'Chase," the title was to launch for several platforms in July 1996 after 18 months of development, but it took developer DMA Design (now Rockstar North) 30 months to deliver and the final product was quite a bit different than the original concept.
Interviewed in 2011, former DMA employee Gary Penn said the game was on its last leg, if not because of stability issues than because it simply wasn't fun. "...The car handling was appalling. There was a point in it where you used to have a button for opening the doors and it was just rubbish. I can't remember if this is true because we used to joke about it that you even had to start the engine. It was awful, it was too sim-y."
One bug, however, proved to be the game's redeeming quality. Lousy pathfinding meant the police would sometimes attempt to drive through your car, which came off as insane and aggressive. Penn described it as an awesome moment because suddenly the police were ramming you off the road, which was more dramatic than them simply pulling you over. The bug was tweaked into a core feature and the rest is history.