On Helping Writers become Authors:

Not every story needs a protagonist who undergoes a sweeping, life-altering transformation. Many memorable tales hinge on smaller, quieter shifts in perspective—or even on characters who stay true to themselves from beginning to end.
Writers often hear that character arcs must be dramatic to be meaningful, but the truth is arcs exist on a spectrum.
Big character arcs can redefine a protagonist’s entire worldview, while small character arcs can reveal subtle but powerful growth that shapes the story in more understated ways. Understanding when to use a big arc, a small arc, or even a Flat Arc can help you choose the right level of change for your characters and keep readers invested from page one.