18: Prius C
There was a short period after the 2008 recession where the Prius was the most popular car on the market. Those days are far beyond us now and the Prius is sort of soldering on as the car that once was. Still ever popular as a brand identity with some, the Prius fails to click with mainstream buyers anymore. With the rise of electric cars and mainstream gas-powered cars getting exceptional gas mileage, few flock to the Prius.

Toyota tried to spruce things up a few years ago with a varied line of Prius models to choose from. These cars were supposed to drive younger shoppers into the Toyota showrooms but all they did was drive a wedge in the already dying product line.