The Dodge Dart and Chrysler 200 were part of a billion-dollar investment by Fiat Chrysler to revitalize the passenger car segment. The problem was that the investment was made 10 years too late, as consumers moved on to crossovers. The Dart was not a bad car initially but the design was smaller than the competition and the reliability was questionable (via Readers Digest).
The Dart was a great concept that utilized a well-known nameplate. But unfortunately, it was built a little too late. By the time Chrysler decided to take passenger cars seriously, the market appetite already moved to crossovers. The Dart was far too unreliable and undersized to be a real threat to Honda or Toyota.