A. Very low income comparing to 100s of hours invested per book. B. Books about those framework are short-lived ones, given trends and versions are changing ra

A. Very low income comparing to 100s of hours invested per book. B. Books about those framework are short-lived ones, given trends and versions are changing rapidly. C. Not everyone are working for a vc funded or FAANGs, but one with such capabilities can definitely work for such.