From wikipedia, "While customer reaction to the EV1 was positive, GM viewed the program as evidence that electric cars occupied an unprofitable niche of the automobile market, evidenced by their ability to lease only 800 units in face of production costs of US$1 billion over four years."
Granted they tried to lease and not sell, but only 800 units leased over four years is small no matter how you cut it. And with only a 55-75 mile range, they only appeal to some urban and suburban dwellers.