Reading my father: a memoir

What is it about a book that catches our attention and forces us to select it and once caught up in its magic, makes it almost impossible for us to put it down /turn it off?
For me, when reading the book Reading my Father:a Memoir by Alexandra Styron, the following ingredients were what drew me to it and kept me enslaved till the last page:
1. the authors great writing style. The apple did not fall very far from the tree with this author. (Her father and the subject of the book is William Styron.)
2. the memories of her childhood growing up around flamboyant parents who lived very full, eciting and tempestuous lives.
3. a book about one of my favorite authors, William Stryon, and one of our greatest American novelists/essayists and author of Sophie's Choice, The Confessions of Nat Turner, Lie Down in Darkness, and many more.
4. a trip though time and her father's life as she researched a major collection of his letters, unfinished manuscripts, and many more items that may have never before been read and had never been published.
           After I fnished this book it made me want to read other memoirs or biographies of authors. Hope that it has the same effect on you.