Recently I ran across a site that talked about 5 steps that people go through after losing a job. I was amazed that coincided with the 5 steps of grief which also happens to excellent method of understanding character arch.
Now this is just an example of what someone would go through after losing something of importance. The key here is how each emotion differs from one another.
This is similar to character in a story. Of course in modern storytelling it is often difficult to portray true change especially for a generation of jaded folkCharacter arch is not deliberate and requires that the writer had some experience in their own life or have researched. This is where writing a character arch becomes tough because many times in real life people avoid pain at all costs. So when someone writes character going through a significant change the audience is slightly on the fence because it doesn't ring true and it doesn't reveal any insight on life.
I recently watched the film, On the Waterfront starring Marlon Brando who gives a really good performance as a ex prize fighter who works as a shoreman. The movie does a great job in showing Brando's character by pitting him against forces that he believes he can't possible defeat.
People change not because of other people but because they want to and they have to. They change because the current frame of mind isn't solving their problems and now they will have to adapt and find a new course to follow. This is the kind of character arch is tricky because it demands that the audience relate to the character as true and credible. Most stories take a short cut and give the character a revelation that isn't all that profound or unique.
The New Alice in Wonderland directed by Tim Burton is perfect of example of quick revelation and instant epiphany. Wonderland starts off as Alice is miserable becauset she has to marry a a guy she doesn't love. So she runs off because that's what women do when they don't want to marry someone. Without giving too much away, Alice's revelation comes a fourth of a way in the film, her epiphany comes much later but it doesn't matter because it becomes difficult to believe this character because the writer wasn't sure what he wanted us to feel about her. Her character arch was dull and it couldn't deliver anything in the way of a new mindset that will change her life. No instead we're left scratching our heads as to what the character wanted. This isn't indepth review of the movie, I'm just using as an example.
Character Arc demands that the character go through a thinking process that people can relate to and that process is disrupted when unanticipated problem arises and pushes the character out of their comfort zone.
I reminded of something I heard about personal change. The moment that a person decides to change is when the river of life engulfs them and they have to figure out how to swim.