"yet the upcoming generation always ends up surpassing their parents achievements"

What do you consider "surpassing their parents achievements"? Sure we may be continuing the technical progress of their generation (i.e., picking up where they left off to go retire), but who's to say that given a greater lifespan, they wouldn't go on to achieve what we have?

If I spent 30 years of my life developing principles of some new science, and the next generation uses these principles to make life better, are they surpassing my achievements?