Grandiose title, I admit. I drive my family nuts because I read the ending first. Doesn't matter if it's a thriller or a romance, I need to check to see if I like the payoff, or I'm not wasting time on the story. A fellow writer was discussing Pathetic Plots, where the main protagonist gets shafted, and my immediate reaction was "oh yeah, an Oprah pick for her book club!" If that's the way the story rolls, count me out.
My daughter has another method for deciding which book to read. If the To Be Read Pile is in danger of toppling, she'll pick three or four and read the first four chapters of each. If she goes to bed that evening, or wakes up the next day wanting to read more of any one of them, then that's the pick of the week. She has much more self-control than I!
My Beloved likes to savor a book. He reads carefully, deliberately, and without a bit of skimming. (Scenic descriptions? Count me out, I'm on to the next paragraph.) Consequently, he remembers each detail about the books he has read and why he liked or disliked them. Me, I remember characters. And endings.
Time is too short, there are too many good books out there, to waste time on a tome that isn't going to tingle my toes. (My alliteration gene has gone crazy. Forgive me.)