For $50,000 miles, you can go 50 miles on electricity, then be just like the 10k car sitting next to you. The cars were prone to catching on fire. The chargers were the issues. They were also prone to breaking randomly, and were EXTREMELY unreliable vehicles. There would be issues such as not being able to make it up a hill.
Only one Chevy Volt ever caught fire, and it was being used in collision and stress testing. Gas-powered automobiles can catch fire following a collision as well.
And they weren't unreliable, they could get as high as 400mpg and there are no reliable accounts of mechanical or electrical issues with them. The reason it failed was because they released a domestic $50,000 automobile during a recession.