> Look at software that has been around for decades, continues to improve, never "needs" a re-write, and will never be re-written. It exists and is not uncommon

> Look at software that has been around for decades, continues to improve, never "needs" a re-write, and will never be re-written. It exists and is not uncommon. Things like the linux kernel, all the GNU utils, emacs, vim, apache, nginx, postgres. They don't get re-written because they can't be re-written without tearing down everything built on top. In every case though there is some newer software out there is inspired by but aiming to "fix" all the short comings of the predecessor.