Back in the day, there used to be professionals known as systems analysts whose job it was to determine the business logic. The information system went through several phases of stepwise refinement. First the requirements were determined: WHO needs WHAT information, WHERE, WHEN, and WHY. (And from WHOM do they get it?) Then, a series of procedures were developed to be implemented either manually or by computer (The "Playscript" format by Les Matthies was particularly useful for the former; standard flowcharts for the latter). Each piece of data, its type, and its purpose was also identified and registered in a standard vocabulary. The programmers only got in on it towards the end: once the major decisions had been made, they wrote the code instructing the computer on HOW to do it. Their focus was on the HOW; the WHAT was not in their job description, and was usually beyond their capability. It takes holistic, big-picture thinking and great social skills to develop an understanding of an entire business division and come up with a plan to implement an information system for that division. The programmers' work entailed about 15% of the total work, and was mainly concerned with the technical details of getting the procedures to be automated running on a computer. These days, with AI, that 15% figure could be reduced even further, perhaps by a factor of five or ten. In the big-iron era, programming was really that simple. The hard decisions had already been made before the first line of code was written. You may think it stodgy and inflexible to develop software this way, but that's how grown-ups did it, and studies showed that it was significantly cheaper than the scattershot, agile-like approach where the programmers where in the lead in terms of systems design.
What's happened since the 1970s is, programming has undergone prestige inflation to the point where programmers are looked to for decisions regarding the actual business procedures, and usually they just don't have the business knowledge or wherewithal to do that. The systems analyst has faded into memory. And as Milt Bryce said, "If this country built bridges the way it builds systems, we'd be a nation run by ferry-boats."