No, this isn't about fictions we construct about the world through software and stories alike. That's a whole other can of worms. This is about work.
When I first started coding, everyone was telling me to draw a flowchart first, and/or write pseudocode. I dutifully tried doing that, but it didn't seem to help me get any code written afterwards, let alone better code.
Later the UML craze started. The only thing I ever managed to do with UML was tie myself into knots with an overly complex class diagram that never became code either.
In the end I learned to simply write code. Because that's what the computer understands. That's how I progress towards getting the machine to play a game, or solve a problem. Everything else is make-believe.
Planning is good, but it's not actually going out there in the field to do the thing you were planning for.
I tried the same with writing. To draw a map first. Ended up with a nice big universe... that was completely sterile. Only one story ever fell out of it. My first story of any significant length, so that mattered, but I struggled to write it and it showed. I wouldn't let anyone read it nowadays. In retrospect it only worked at all because it mostly focused on one little corner of one world.
I tried again later with the same universe. This time it resulted in a big nice RP that became a novella in turn. And another story by a friend. It was progress, but it still didn't get me far.
Conversely, the universe I have now started with a story. Just one little 1700-word fanfic I started writing on a whim, intent on just going wherever it would take me. That turned out to be a vast playground full of adventure. Go figure.
My old setting isn't gone, mind. It survives in the planet Mir from Parole Planet, and the Dhiira warrior-monks. But that, too, fell flat when I first tried to write a story about the world itself. Sufficiently Advanced Technology came out stilted: another story I wouldn't let anyone read now.
In writing, too, no amount of planning, outlining or worldbuilding can substitute for the actual work of bringing your creation to life. Sooner or later you have to buckle down and just write. A little preparation can help sometimes, but here's the trick: prep work is often invisible.
All those bad old stories I wrote? None of them was wasted; they were all practice, and gave me ideas to reuse.
You don't prepare for a hiking trip by reading travel books and buying ever more fancy gear. Grab any backpack, don an old pair of boots and head outside for a walk just out of town. If something doesn't go smoothly, you can fix it before the next sortie. But only from hands-on experience.
Besides, you need the exercise no matter what. Can't get it any other way.