Part of it was that each source wanted to be able to audit _their_ money, and have traceability. So in some sense it was just what you say, but that roughly do

Part of it was that each source wanted to be able to audit _their_ money, and have traceability. So in some sense it was just what you say, but that roughly doubles the amount of work done for accounting software. It also meant that most private-sector software was insufficient for the task.