At an old job, they were using an older XML marshalling library that hadn't been maintained in years, but it was everywhere in the code. Well, it finally got to the point where the thing just stopped working (some schema it couldn't parse), so somebody suggested that we "refactor" the code to use the more standard, well supported JAXB. Well, since we're talking about a couple million line code base that parsed XML literally everywhere, the refactoring ended up taking months (mind you, this was something we were completely dead in the water if we didn't do). However, it got into management's collective hive mind that refactoring = several months of no new features, so they prohibited anything called refactoring.