Certainly. One could consider that any large team complex system that has functional requirements determined (and best understood) by external domain experts, is likely not understandable by software developers. This is exacerbated by our industry having no standard way to map those complex requirements into executable code.
The result is likely some big ball of mud, partially understood by the (now gone) original developers. One that is hacked at and refactored at the edges by those who inherit it.
Consider an actuarial risk calculation model, a payroll system, an air traffic control system, or perhaps something simpler like a model of a double-entry accounting general ledger. Could you wholistically understand the code base of a double-entry accounting solution?
Such large complex systems cannot normally be rewritten economically prima facie. Instead if possible, typically small parts are carved off, rewritten and delegated to, until the economics and inability to add new features absolutely force some attempt at a rewrite.
The result is likely some big ball of mud, partially understood by the (now gone) original developers. One that is hacked at and refactored at the edges by those who inherit it.
Consider an actuarial risk calculation model, a payroll system, an air traffic control system, or perhaps something simpler like a model of a double-entry accounting general ledger. Could you wholistically understand the code base of a double-entry accounting solution?
Such large complex systems cannot normally be rewritten economically prima facie. Instead if possible, typically small parts are carved off, rewritten and delegated to, until the economics and inability to add new features absolutely force some attempt at a rewrite.