A career is shaped like a big S
When you start out, you are at the top of the gentle Scurve, full of idealism;
you want to Save the world.
Mid – way, starting to slide down, you largely just want to Save your ass (stay out of trouble and the courts).
Near the end you have returned to idealism and want to Save the world again.
Eugene[sic] – From http://www.worldortho.com