Mercury was one of the most successful brands of the Ford Motor Company. The Mercury brand launched to compete against Chrysler and Buick. The cars weren’t basic and they weren’t luxurious; it was a happy medium. The original Mercury models like the Monterey were unique, but as time went on, they became badge-engineered Fords (via Motor City Garage).
Toward the end of the brand’s life cycle, the cars were nothing more than Ford models with upmarket trim options. The Mercury brand never had a focus in the Ford portfolio. The final model, the Sable, didn’t excite anyone.