I agree, and that needs to be done in both cases. A complex business logic system has an awful lot of unknowns because it’s never been built before. While syste

I agree, and that needs to be done in both cases. A complex business logic system has an awful lot of unknowns because it’s never been built before. While systems that talk to similar problems might have, businesses are highly complex in themselves and even the users usually can’t articulate how things actually should work or why. They usually can only explain what they like or dislike about the small part they do in their job. That’s much harder than a brand managed layout rendering. Edit: the hardest business logic is actually brownfield development - where the users who knew why don’t exist any more, and the developers who figured it out have moved on. I think these are the hardest to predict efforts with the least management margin of error for prediction mistakes. It also, IMO distinguishes between a good engineer and a great one. A good engineer can write code. A great one can improve code that been improved by hundreds of different people over decades.