An aggressive and demanding manager, Piëch was known for setting both lofty and extremely specific goals and standards for projects. An example of this is with the development of the Volkswagen Phaeton luxury car, in which Piëch laid out ten parameters the car had to meet, amongst them being that the Phaeton should be capable of being driven all day at with an exterior temperature of whilst maintaining the interior temperature at . Piëch requested this even though the Phaeton's top speed was electronically limited to . Another requirement was that the car should possess torsional rigidity of 37,000 N·m/degree. Piech would often become personally involved in vehicle development, such as how he oversaw the development of the Audi 100's aerodynamics himself, keeping it secret from even Audi's top engineers to prevent any crucial details of the car's aerodynamic capabilities from leaking to competitors. Piech often liked to ride along with automotive journalists during press test drives and would consider their critiques to improve Volkswagen's vehicles. "Car and Driver" writer John Phillips recounted how when he test drove the Volkswagen New Beetle during its launch in 1997, Piech rode along and asked for his opinion on how its chassis and driving dynamics could be improved. Similarly, Piech once demanded that an "Automobile" reviewer take the Volkswagen Phaeton up to its top speed while he rode along in the back seat.