Robin described the “character flaw” as the belief, need, or fear that shapes a character. It is the barrier that keeps him from moving forward. It determines how he makes decisions, and, for better or for worse, is the essence of who he is. Examples of character flaws are the “belief that love is conditional” and the “fear of failure.”
a character’s “flaw” is the source of both his greatest strength and his greatest weakness.
A plot development method that suggests characters should "cross over" and experience "near death" at certain points in the story line. It makes a good argument by citing book and movie examples.
Take that advice beyond the beginning stages, though, and what you get are stories that really should move the reader but don’t, either because the emotions are all related from the outside or because the narrative doesn’t provide the sort of dense, information-rich substrata upon which complex characters are built.
Which leads me to my second point: Your story is about Gina, at forty, deciding whether or not to leave her boyfriend. Are you really going to spend half your story showing us Gina’s white-trash childhood in Elbridge, Michigan (a key bit of backstory)? Or are you just going to cut to the chase, provide a few key details, and move on?
But push this advice too far, and again, you’ll get stuck writing mediocre fiction. Because sometimes the things that don’t work are actually important. They don’t work not because they’re the wrong things, but because they’re the hard, ambitious, at-the-very-edge-of-what-you-even-know-how-to-say-things, and the only way to land them is to dig deeper, work harder, and sometimes even (god help you) add rather than cut.