Oracle / IBM had an existing working payroll system to copy. All they had to do was reimplement it in modern hardware and software. Some government employee in Miramichi might not have been happy because oracle didn’t listen to what they thought they wanted but if the contract has been to deliver a system that produced the exact same output as the old one oracle/ibm would have no excuse for not having a successful project.
It is astounding nobody was fired for this.