I have that book. Yes, its doesnt always explain the "why's", but it is
titled "fundamentals" for a reason. Its just to get you started with the
program. Ive been told, and have noticed myself, that maya requires alot of
experimenting. If you do enough examples from tutorials you will learn how
to do basic things. Its not going to come to you instantly. But just keep
at it. I am learning more everyday and Im seeing improvements from working
with the book and what i find online etc.