“It requires quite a leap from standard journalistic reporting for a writer to say: I can understand another human being, my character, well enough to put the reader inside that person’s mind.”
Jon Franklin, Pulitzer Prize winner in two categories for his science writing, 
discusses the important use of characters, in his short essay in “Telling True Stories.”
As a science writer, Franklin describes the levels of understanding characters as rigorous and that the psychological interview is an important part of the process. This type of interview answers the question of: What made this character into the person he or she is? In a sense, it is a history-taking process.
This helps writers to draw a true portrait of their character. Although many facets of the character may not pertain to the story, it is necessary in getting readers to enter the story through that character.
“The most powerful thing literature can do is move people to suspend disbelief,” Franklin said.
Readers forget where they are and immerse themselves into the story through the main character. And understanding the subject who will become the main character is key.
“Description alone isn’t helpful.”
Franklin says that the challenge of narrative writers and journalists, is that they must tell readers how a character’s world stacks up against the external reality they face. To create this character, it first comes from reporting–from observing externalities. However, drawing on details of a person’s surroundings (such as a golf trophy on their office shelf) does not accomplish this type of reporting. The writer/reporter must understand the significations of those surroundings. With that said it is the character’s motive that comes first. The meaning or the why is secondary information.
When writing, writers are first attracted to a plot. Second, comes the character/person responsible for the plot action. Franklin says, “If the writer thinks more deeply about character, and especially the relationship between plot and character, the story becomes much richer.”
That richness comes back to moving the reader to suspend disbelief.
Kelly Sherrard Online 