Like onions and ogres, good stories have layers. Often we think of these as storylines. While there is generally an overarching theme, like love conquers all or persistence pays off, and a main storyline central to the theme, there can be (and generally should be) additional storylines which heighten the tension and add depth to the novel.
Often these secondary storylines center around characters other than the main character. Each character needs to have a distinct personality with their own strengths, flaws and hurdles to overcome. Consider, for example, the theme “home is where the heart is,” and a main character who runs away in search of the ideal family (one where she’s never scolded.) She may encounter a number of people and situations that ultimately lead her to understand that the family she ran from is where her heart was all along, but during her excursions, she may meet a boy who lives in an abusive home. That just added a whole new layer, because we now have a character with different needs and hurdles, a new character arc to deal with and a new understanding of “where the heart is” for this character. Then the tricky part begins–weaving the two stories together seamlessly to a satisfying end. Take it from one who knows…it’s much easier to build your layers in while writing the first draft. I’ve been in the position of realizing after I wrote the words “The End” that my story fell short, and I knew why. I knew I needed at least one more layer. I figured out what that layer should be, and oh how I wished I’d incorporated it in the first draft. Did my seat-of-pants writing style contribute to the oversight? Probably to some extent, although I’ve met outliners who admitted to having done the same thing. Not to mention highly respected authors. I once read that Barbara Kingsolver went back and added a character to one of her novels. The knowledge didn’t make my job any easier, it just made me feel better. So before you start your next novel, remember…good stories have layers, and thinking them out carefully ahead of time will save you lots of time and aggravation.