Why is most everything remastered?

I enjoy most remastered CD or lp to quote Robert Healey in his most recent TAS review " the best remastering jobs are transformative. You hear a new found clarity; each instrument or voice is distinct and sonically separate; the bass suddenly has depth, texture, pitch and naunce...."  I completely agree with his assessment.

Don’t forget most of the music released in the 50’s and 60’s was meant to sound good on a 3" car speaker or mono record player.