It was rather hard for me to find those out when I built my first cmake-using package.
Contrast this with ./configure --help, which is very clear to a newbie in comparison.
Of course autotools has had a decade or two of refinement.
FWIW, the easiest new-project setup for me has been qmake.
That's familiarity. autotools is a baroque answer to a problem that's just simply less screwy than imake was. More to the point, autotools is really only Linux/POSIX centric. It doesn't do well outside of that- and sadly, you DO have to deal with Windows for some things... (We won't get into the fact that autotools is two kludges on top of ./configure that were done to compensate for ./configure and Makefile deficiencies...)