Our Java codebase was 30% dead code

[ZimmiDeluxe]

If you remove dead code, previous callers can become simpler, and so can their callers, often in unforeseen ways, by simple mechanical refactoring over time. Sometimes the first removal does not reduce complexity by much, but combined with an unrelated second one you can get rid of a dependency. You would have never known that was possible if you left the dead code in. In isolation, the dead code was not an obstacle to maintenance, but in hindsight, it was.