The Volt is a pretty car but it’s just too expensive and too Me-to to gain real share. The Prius is a Toyota and as such, up scale yuppies don’t feel down class when driving it, they feel virtuous.
While the Chevy Brand is beloved by many middle class Americans it’s loved for its trucks and muscle cars, edgier yuppies buy Cadillacs. If the Volt had been a Caddy and a bit more of everything: bigger, striking, powerful, EXPENSIVE it might have had a better chance. Yuppies feel dissed in a Chevy, however green, and the Red Staters aren’t going to buy a smaller, slower, more expensive car when they can get one of the quality new generation GMs, Fords or Chryslers for a few pennies more or less.