For some reason, I never could do the exercises of programming books. When I started them, in the end I had a completely different program that solved something that affects me.
I also could never read a programming book from the start to the end. When I used the language a lot and used the book as reference, I read all the pages somewhen in a several months interval, and in some random order. When I didn't use the language a lot, I just didn't finish the book.
Nowadays the best reference is online, so while books are still good for giving me a start, there is a long time that I don't finish one.