The Great Artists -How Long (Or Short) the Visit?

Upon hearing of the recent passing of Elliott Carter, the unanswerable issue of longevity, or lack thereof, is one of fascination to this writer:
The career of Elliott Carter, one of America's most defining composers, was immeasurably enhanced by a life span of 103 years, allowing for an  unprecedented opportunity to promulgate an array of  tactics and approaches in the art of composition - how many composers have lived this long, writing veritably to within weeks of their passing?
And in the same breath, Mozart was given barely 35 years to establish his immortal signature  in the Book of History.
And Schubert, given even briefer a role; having left us in his 31st year.
Chopin, complaining of "a short life and a long nose" completing  his journey in year 39.
Or Schumann, at age 46.
In the world of performance, the giants Lipatti and Kappell in their early thirties...
While on the other hand, Artur Rubinstein, terminating his career at age 90, citing his being "tired" of  performing because of frontal blindness, even though his playing remained at world class level until the day he "retired."
Other examples exist; however, this writer has grappled long enough with the issue of Longevity and Brevity, as no answer can ever be made available to those left behind...