Although I can not tell you exactly why many people want stiffer suspension package for the car that they drive every day.
People often update their suspension, so your car can handle better. Basically – we learn that loosely manipulation is simply a matter of traction. (Putting rubber on road.) Traction allows us to do all sorts of fun things, on different types of road surfaces. Of course, different suspensions work best under different conditions.
On smooth surfaces, the car will handle well, and tyte ryde will be quite hot looking with the new aero kit and wheels blingin. Once you take the right to a bumpy road, ride quality can become unbearable rough as car rides and bounces all over the place. This can cause a hernia or headaches.
On a more serious note, if you have to brake hard or turn on the bumpy road, the springs are designed to absorb shock, they will not do their job and you will lose traction. This is very dangerous and can cause you to get in a serious accident.
However, most of the roads especially highways are very soft. Sometimes you may get the occasional hit, but mostly you will have a very smooth stable ride. You will be able to take good sweeper along at a comfortable speed and do not have to sweat.
Take the bad situation of the city and the highway and is multiplied by a million if stiff suspension and mountain roads mix. These roads are generally not well maintained, and $ 2,000 racing suspension really going to work against you here. The car will be bouncing because of the bumps and the springs can’t absorb them. Weight will spread all over the place, so you will need much leverage as you can get.