People mostly say that the characters of a story have to be developed first, but I don't really understand why characters play such an active role. Can't the characters simply be classified as objects?
The main distinction to be made here is between character-driven stories and plot-driven stories.
Character-driven stories, as you can imagine, focus mainly on the characters, their struggles, their growth and their relationships. The central questions of these stories could be, What will Bob do in this situation? Will his relationship with Alice survive? How can Charlie react to such an event? and so on. In this case, there must be at least a subset of characters (e.g. the main cast) that have to be well fleshed out, so they can't be classified as objects.
Plot-driven stories, on the other hand, tend to put more emphasis on the plot. The main question could be Will the great evil be defeated? Can this nation win the war? Can the police stop this killer? etc. Characters are less central in these kind of stories.
For example, a lot of detective stories revolve around getting the guilty in jail. Those stories do have interesting characters (a troubled detective, his steadfast colleague, a shady informer, the witty morgue doctor, and so on) but developing this character is not the point. The point is the current case (in other words: the plot). The main character in those kind of stories usually gets some development, but its often diluted in a series of books rather than a single one.
So, in a way, characters are instrumental in pushing the plot forward.
Yet I wouldn't say that characters may be considered objects.
Even when you're writing a plot-driven story, whether it is a thriller, an action packed adventure, a war novel or a daring science fiction, treating your characters like disposable objects is a risky operation at best.
The audience won't feel engaged towards characters who are as shallow as cardboard. Shallow characters are bad for a story since they can dim a good plot.
Another risk is that if you don't define your characters, you risk making them inconsistent. Good stories are made up by conflict, but it has to be meaningful conflict. Characterization is a tool that helps you determine what choices a character should or should not make; and which character should move the plot forward.
If your cast is just a bunch of faceless puppets ready to do anything that's needed to advance the story, the audience will notice.
Writing stories is all about evoking feelings and emotions in the reader - specific emotions you want to evoke with your story. That's what sets a story apart from a report, which is to state facts, be informative and neutral. Writing a story like one writes a report is one of most common, fundamental errors of beginning writers. The writing is dry. The reader's reaction to such a story is "Okay, so that happened. So what? Why should I care? I wasted my time reading this."
Developing a character is one of best ways to form an emotional bond between the character and the reader - a feeling of fellowship, identifying as the character, compassion - or even just cold hate for the character. With such a bond the events of the story have an impact, they cause emotions, make the story enthralling and unforgettable. Without that? Blah. Something happened somewhere to someone, nobody cares.
Orson Scott Card described 4 types of story he called M.I.C.E. The goal is not to exclusively write 1 type of story, but to be aware which type your story is, and then work to include some of the other types as support. The technique is called M.I.C.E. Quotient.
- Milieau ("big genre" setting, journey, time/place)
- Idea (transformative inventions, What if…?, alternate history)
- Character (internal conflict, want/need, protagonist/antagonist)
- Event (catastrophe, political change, external conflict)
Mary Robinette Kowal has adapted this idea into a nested structure called M.A.C.E., and she breaks down how each of these story-types are expected to open and close. She goes further by explaining that each element needs to close (in her words: "be answered") in the reverse order that they opened (each is nested within another). https://www.youtube.com/watch?v=yAJT_-gpG4U
What both authors emphasize about these structures is that it's extremely rare to find a story that ignores 1 or more of these narrative elements – when they do exist, they aren't very good. Card and Kowal are considered experts at analyzing and writing fiction, so I offer this answer so you can do more research and decide if and how to add these techniques to your writing.
My personal advice is if you honestly have no interest in developing empathy for your characters, and prefer to move them around as objects like chessmen, you might feel more at home writing for a videogame or RPG where the "characters" are blank slates.
If your characters are interchangeable, forgettable and one dimensional you will have trouble getting readers to read much of your book.
Readers meet a character and watch, waiting for something to happen. If we don’t care enough about the character because they are just a placeholder, we put the book down.
Plots happen to someone and if that someone is an undeveloped element and not a character, we don’t care.
I was reading a book set during the French Revolution - it had a strong plot and a few interesting characters, but others were rather flat. I read on because one character was a young nobleman with republican views who joined the revolution. The author killed off a lot of interesting characters, but I kept reading because this guy had a problem and I wanted to see how it was resolved. I cared about him. She killed him off too and I put the book down - no one left I cared to follow.
Memorable characters are either hard work to create or they come as inspiration. They fuel even the most plot driven story - they are the reason the reader turns the page.
My piece is a character driven thriller and before I started writing it, I spent weeks thinking about two characters (one is minor, yet pivotal). I had a clear plot and my characters and I started writing. My characters reached a point where they diverged from the plot, essentially telling me they had a better idea. They did and the book went in a direction I had not foreseen.
My point is, had I held to my original plot, forced it to play out as I had planned, I would have 80k words of a generic novel that I would probably not want to read - at least, not twice. Following my characters, I have a much longer work that I am proud of, enjoy reading, and is fun to write.
I have no idea how it will end, suspect I will slip the original plot in sometime in the future and trust my characters to tell the tale. It is their story, I am just writing it.
No, characters aren't interchangeable. If they are, nobody wants to read it.
The plot happens to the characters, and people read to identify with the characters, as people, and they develop feelings for them (good and bad). Even in a plot-heavy story line, like those used in the current series Elementary (last season airing now; a Sherlock spin), the crime and how it was done is the "plot", but almost unimportant: Fans like that the plot is usually very clever, but what they remember about episodes is how the relationships develop: Joan (Dr. Watson) is unhappy living in London, Sherlock is concerned, Marcus stages a private intervention with Captain Gregson over his treatment of Sherlock, Sherlock tries to address some of Joan's complaints about the DI, and the cliffhanger: Captain Gregson gets shot, and might not make it. Next mystery: Who shot Captain Gregson?
Let's see, what was the crime in this episode? I forget, Sherlock solved it somehow. What we are watching is a man with an extraordinary skill that struggles with personal relationships but as a consequence of that values the few he does have all the more.
I'll say it again: Plots happen to characters, and that is why people are reading the story. In Harry Potter, the magic setting is very clever, the plots are basic mystery, but we are really reading to see how those things affect Harry Potter, Hermione Granger and Ron Weasley (and a handful of others).
If you treat your characters like objects or chess pieces, nobody will care about them. When they stop caring what happens next to your character they will put the book down. Because it doesn't matter what happens next in the plot, if they aren't rooting for anybody, and aren't frightened for them, or frightened of the villain, then it isn't going to change anything for anybody they care about.
On the other hand, the more characters they DO care about, the less likely they are to put the book down.
I often say here, what keeps readers turning pages is wondering what happens next. How the scene will work out, how the chapter will work out, and eventually how the Act or whole book will work out. But the biggest reason they want to know what happens next is because it will have an effect on the characters.
You do have to have a plot, so something happens to the characters and readers can anticipate things happening to the characters. Complex and clever plots are entertaining; they keep the uncertainty of what happens next to the characters at a high level. Elaborate imaginative settings can be entertaining, they keep the reader wondering what they will see next, and often present fun problems for the characters to deal with.
Without characters to care about, those elements are worthless.
First. If you develop the characters first, the plot first or do them iteratively... or just start to write and then edit to make the characters work in the final version is completely a question of taste and writing style.
You do not have to create the characters first.
You should, however, as I will get into below, have well-developed characters, plot, and theme to make the story work.
As has been mentioned in other answers, you use characters to create an emotional response in the reader and a connection with the story. However, there's more to it than that.
If you don't utilize characters fully in your story you're losing half your set of tools to create conflict. You're also making it much harder to make the theme of your story work. In the worst case scenario, you risk making the whole thing limp.
Inner conflict vs Outer conflict
A story usually has two versions of conflict. The inner conflict, taking place in the head of the character, and the outer conflict taking place in the world outside the character.
An important aspect of the inner conflict is about character development (a.k.a. change arcs). This development is usually about how the (main) character stops believing in the lie of the story and starts believing in the truth (positive change arc). Other versions exist; truth to lie (corruption change arc), lie to worse lie (fall arc), lie to depressing truth (disillusion arc).
The outer conflict is, in short how the characters (protagonist, antagonist, and various sidekicks) try to make their lies and truths manifest in the physical world.
The Flat Arc / Testing Arc
Apart from the above versions of character development, there's also a version where the character defends their truth against a lie-ridden world. This is called a flat or testing arc.
This type of character development is what you'll see in superhero stories, and may also be common in plot-driven stories. It may seem as if there is no character development, and there isn't... in the main character... but instead, it happens in other supporting characters around the main character.
Character development is all about the character changing their relationship to the truth and the lie in the story, however, even a flat arc character can evolve, learn new skills, become more confident in their truth, or more skillful in using it, they just never exchange their truth for the lie. Not even when they are sure their truth is about as effective against the lie as a straw of grass against a tornado.
Of course, just because the character doesn't change, doesn't mean they don't get a thorough beating in the story. They usually get to pay dearly for daring to believe in the truth. Sometimes even with their lives.
Character, Plot, Theme
The three elements character, plot, and theme are among the more important in a story.
The theme can be described as the conflict between a truth and an opposing lie (or the conflict between a group of related truths and an opposing group of related lies—it can get more or less complex).
The trick with the theme is to weave it into the story so skillfully the reader almost isn't consciously aware it's even there.
There are many ways this can be done but in short, it's about showing, not telling the lies and truths. If your characters never utter them in dialog, great! Or at least not have a long monolog about them... Instead, make the reader understand what the characters believe by their actions.
The theme connects to the characters by having the truths and lies cause character development.
The inner conflict consists of the protagonistic and antagonistic characters being proponents of the truth and lie respectively.
The outer conflict, the plot, is about these characters doing things to try to manifest their lies and truths in the outer world (i.e. shaping the world according to their beliefs). In doing so, they make the outer conflict a manifestation of the inner.
Without this triangle of theme, character, and plot, the story is at risk of seeming limp, illogical and/or superficial. Not to mention that with less developed characters it will only contain half the amount of conflict you could otherwise pack into it.