It's hard to notice sometimes when looking at the final story, but there are at least two approaches to write them. Starting with the events, or starting with the characters.
(soruce: pixabay)
I'm not an expert and most of this info is from my humble experience (I'm just a beginner writer)... from articles I read, and from watching SMAC videos (those encourage manga writers to use the character approach). I also noticed that the protagonists of the manga Bakuman (a story about manga writing) use the plot approach where their rival uses the character approach.
Plot Driven Approach
As a writer, first you imagine the story, the events and the action... If you write the idea or the summary of the story you leave out the characters.. at the moment they are just roles.
When you write the story you turn these roles into characters. you make characters specifically for that role so you create a personality and a backstory that makes that role possible.
Plot Driven Approach is good way to create new ideas. and to have a specific ending. But it's very easy to make your character act out-of-character. especially in longer stories.
Character Driven Approach
As a writer, first you create the character, their personality, likes and dislikes.. you create a backstory for them. If you write the idea or the summary of the story the character would be the base of it.
And finally you put them in a situation... and see what they do in that situation.
Sometimes you can't predict character driven stories as you write them, these characters aren't made for a "role" so they might act differently in some situations, being fleshed out this much it's easy to make them act out-of-character if you try to make them act roles to reach a specific ending.
The more characters you create with this approach the more unpredictable and real the story becomes. But it's hard to control the action this way.
Double Approach
I think most of the writers use both approaches at the same time...
For me, I always start with Plot Driven Approach, but as soon as I create the characters for the roles I go fully Character Driven....
Most of time nothing from the actual plot stays as my characters always act different than I want them to. It doesn't feel right to make them do something they don't want so my story writing is filled with imagining and re-imagining different endings until the story reaches an ending by itself.