I also started shaving with a full head of hair - almost.  I had thick and unruly hair - very wavy, but not really curly.  It was too much curl for all the popular hairstyles at the time, but not curly enough for the curly for the curly styles.  I was too chicken to get a perm (yes, guys getting perms were popular then).  I likes shaved heads on guys, but was to chicken to shave it off without the excuse of balding.  I was one of the guys that conformed to the norms of the day, too chicken to do anything the may be considered outside of the norms for a conservative professional man.

So I decided in my early 30's that if I ever started thinning, I would shave it off.  My hair remained thick through my 40's, but I could notice it was thinning (mainly in the crown area) in my mid 40's.  I think I was 49 when I shaved and instantly loved it.  To the public, I still had thick and full hair.  I had no thoughts or desire about growing it back, although I would periodically let it grow a few weeks just to see how the balding had progressed.  By 53 or so, the top was completely bald.  So I completely avoided the bald fringe look by shaving early.