9: 2006 Chevrolet Monte Carlo SS
The next generation of the Monte Carlo SS was a carbon copy of the car that was in production for the previous six years. The new generation of the Monte Carlo SS did bring back the V8 engine. But it was a modern V8 engine, and critics panned it for lacking the necessary horsepower and performance to be a real sports car. The styling was also panned by the critics, who felt the car was just an outdated rehash of the outgoing model (via Top Speed).
The Monte Carlo was discontinued only a few years after it was released. The sales numbers were not what GM had hoped for since the car was not moving units. It appears that consumer tastes had just changed from what they were when this car was originally released. The Monte Carlo had a storied history at GM and this example of the car was just plain disappointing.