Learning the craft

Just finished reading a couple of books by a duo that have become very successful. While I was reading them for pleasure, my real motivation was analyzing what they are doing that is right in the hopes of learning what makes a good book. It never hurts to learn what makes one book great and the other ho-hum. Of course, the goal is to join the ranks of the great.
As everyone says over and over, the key is characters and conflict - make a character or characters that the reader cares about and put conflict after conflict between them and their goals until the end.