Everyone keeps saying 80/20 but that undersells what's going on. The last 20% isn't just hard. It's hard because of what happened during the first 80%.
When an agent takes a shortcut early on, the next step doesn't know it was a shortcut. It just builds on whatever it was handed. And then the step after that does the same thing. So by hour 80 you're sitting there trying to fix what looks like a UI bug and you realize the actual problem is three layers back. You're not doing the "hard 20%." You're paying interest on shortcuts you didn't even know were taken. (As I type this I'm having flashbacks to helping my kid build lego sets.)
The author figured this out by accident. He stopped prompting and opened Figma to design what he actually wanted. That's the move. He broke the chain before the next stage could build on it. The 100 hours is what it costs when you don't do that.
This is how all software projects play out. The difference is when it's people we call it tech debt or bad desing and then start a project to refactor.
Apparently LLMs break some devs brains though. Because it's not one shot perfect they throw their hands in the air claim AI can't ever do it and move on, forgetting all those skills they (hopefully) spent years building to manage complex software. Of course a newbie vibe coder won't know this but an experienced developer should.
Except when you've worked on building the software yourself instead of getting the LLM to do it, you have a loooooooot of built-up context that you can use to know why decisions were made, to debug faster, and to get things done more efficiently.
I can look at code I wrote years ago and have absolutely no memory of writing it, but I know its my code and I know where some of the warts and traps are. I can answer questions about why things work a certain way.
With an LLM, you don't get that. You're basically starting from scratch when it comes to solving any problem or answering any question.
When an agent takes a shortcut early on, the next step doesn't know it was a shortcut. It just builds on whatever it was handed. And then the step after that does the same thing. So by hour 80 you're sitting there trying to fix what looks like a UI bug and you realize the actual problem is three layers back. You're not doing the "hard 20%." You're paying interest on shortcuts you didn't even know were taken. (As I type this I'm having flashbacks to helping my kid build lego sets.)
The author figured this out by accident. He stopped prompting and opened Figma to design what he actually wanted. That's the move. He broke the chain before the next stage could build on it. The 100 hours is what it costs when you don't do that.