> The problem is that in programming the discovery part is often 90% of the task. That's exactly it. Scoping out the solution is 90% as hard as just doing it.

> The problem is that in programming the discovery part is often 90% of the task. That's exactly it. Scoping out the solution is 90% as hard as just doing it. By the time you've figured out enough of the details that you're sure there are no more surprises waiting... you're just about done. I suspect that a lot of counter-examples people have witnessed are examples of poorly factored codebases. I've seen teams/projects where they estimated projects accurately because the "new" thing being created was a slight variation on a kind of thing they'd created many times. For example, I once worked for a company that generated e-commerce sites for clients. They'd make a new one basically by copy/pasting an existing site from another client and changing some text/images here and there. Super predictable after doing this a bunch of times... but also a maintenance nightmare having dozens of slightly different codebases. And how do you iterate? They couldn't evolve. Shopify ate their lunch. I bet Shopfiy has a really hard time estimating the time to ship a new feature. But they add it once for everybody.