Much Backstory Do You Create Even If It Never Makes It Into the Final Draft?

Every time I start a new story, I fall into this weird rabbit hole of backstory.

I’ll build entire timelines. Family trees. Maps. Hobbies, habits, traumas. I’ve written pages about a character’s childhood best friend who doesn’t even appear in the actual plot. It’s like I need to earn their voice before I can write it.

But here’s the catch: most of it never makes it in.

At first, I thought that meant I was wasting time. But over the years, I’ve come to believe that invisible work shows up between the lines. A character’s behavior feels real because I know why they act that way, even if I never say it outright.

This reminds me of a product copywriting job I did for a startup that sourced handmade goods through Alibaba. The founder had a whole story about the artisans’ training, their village, even the history of the dye techniques. I used maybe 10% of it. But knowing the rest helped me write copy that felt grounded and respectful, not generic.

So now I don’t fight the impulse. I build what I need to feel immersed. If it doesn’t end up in the draft, it still lives under the surface like scaffolding you remove once the building stands.

Do you write detailed backstories for your characters or worlds? Do you use that info in the narrative or just let it shape the subtext?