Comment by arnorhs

Well the UI-first thinking makes more sense, since in most cases you are solving process-problems, which involves "what does who do when?"

It's hard to communicate a process through a REST API. Sure you could document it incredibly well, maybe even have every part of your ui represented by an API endpoint, but ultimately, due to the number of customizations involved with each ERP view, you'd end up with some sort of bastard, which was never quite the same as the real deal.