> Every project that I know of that focused on replacing mainframes running Cobol quickly reached nightmare-like complexity during the analysis phase - especially because the original developers were uncooperative and the scarce documentation was obsolete
That has been my experience as well. It's also the case that business processes get designed around the COBOL code, not just vice versa. Separating out what are actual business requirements from "what we've always done on the mainframe" can be fiendishly difficult, and not just the original developers but the customers can be extremely uncooperative. It takes management coming in and saying "these are the new business processes, they are compliant with the industry standards, and our new software is going to implement them" to get things to actually happen. How that works for a changeover in something like a bank is beyond my experience, though.
That has been my experience as well. It's also the case that business processes get designed around the COBOL code, not just vice versa. Separating out what are actual business requirements from "what we've always done on the mainframe" can be fiendishly difficult, and not just the original developers but the customers can be extremely uncooperative. It takes management coming in and saying "these are the new business processes, they are compliant with the industry standards, and our new software is going to implement them" to get things to actually happen. How that works for a changeover in something like a bank is beyond my experience, though.