Lately I have been watching on YouTube some of the video segments that were recorded by Martha Alderson, who has been called "the Plot Whisperer." Her blog where you can find links to this series of YouTube videos is: http://plotwhisperer.blogspot.com/
In the first of her videos titled "Dramatic Action Plot," she focuses her discussion on determining a character that the writer wants to write about. The second video in the series furthers this discussion and talks about character flaws. I found this interesting because she is known for discussing plot rather than character development and yet she was advocating starting with a character and developing the plot from there. She talks about that the writer needs to know this character and their goals. In addition the goals cannot simply be goals, but need to be driving passions. So if the character is a mystery detective, it must be that character's driving ambition to solve the case.
In Randy Ingermanson's Snowflake Method for creating fiction his first step is to write out a one sentence description of the story or novel. This sentence is then expanded into a summary paragraph for the second step. Creating characters is a third step. In many ways he starts with plot and then populates the story.
So which approach is better?
I think both methods have merit. Without good characters a story will fall flat. Plots that are unsatisfying or do not contain all the Aristotlian elements of a story are unsatisfying. In my opinion it depends on the story that an author wants to tell. If the story is to be primarily character driven and have as one of its features a primarily internal plot, then I think that starting with developing a character or characters makes the most sense. If the story is to be primarily plot driven, determining what the plot will be and then creating characters that will best carry out that plot is the way to go.
I have two characters who I began thinking about and working on quite awhile ago. I can close my eyes and envision each of them. I can imagine how they speak and how they would respond to certain events. I am very intrigued by these characters. I think they are compelling and I want to do them justice and put them in captivating novels. The plots for both of these characters out of necessity for who they are as characters-- their conflicts, fears, goals, backgrounds, and concerns-- need to be action driven, external plots. I am finding it incredibly difficult to write their stories in part because I started with the characters and the stories for them will be not internal plot driven stories. Perhaps as I gain more skill I will be able to create the stories for these characters. The more that I write and think about things, the more I learn.
Another danger in creating the characters first is that the author could create what are called Mary Sues. Mary Sues are so idealized that they never approach feeling authentic and it feels a little like the author is fantasizing through them. Writing stories is not about making idealized versions of oneself who can never be defeated and always come out smiling. On the contrary on some levels it a little sadistic in that the writer has to really put the characters through a certain amount of hell. A story needs conflict and if the writer likes their characters too much, they will shy off of putting the screws to the characters. If the characters are idealized versions of the author, why would any author inflict torment on themselves even in their fantasies?
Starting with the plot also has pitfalls as well. A writer can write out a pretty logical plot with external action scenes that seem to flow consistently. And then they create the characters for the plot and even if they create those characters specifically for that plot, the internal logic of the characters interacting with the pre-planned external plot may require more thinking and changes. Also if the story is too externally driven it may feel like it does not have either an empathetic main character or an emotional center to the story. I think a great deal of science fiction and action thrillers start with plot and are subsequently populated with characters and sometimes the characters are less than authentic.
Again, I think both methods of developing stories have merits and choosing which will fit the writer's current project makes the most sense. Ultimately in the writing of the story or the novel there will be an interplay between character and plot development and the writer will have to move back and forth and revise things as they go. Both characters and plots are important to make stories work.