"left alone" corresponds to how it was designed. Your task is to push the code a little closer to the design, which always has compromises in implementation.
The big fights come in (as seen in comments in this post already) when there was no original design, and it's mess vs possibly dubious attempts to clean up the mess.
The big fights come in (as seen in comments in this post already) when there was no original design, and it's mess vs possibly dubious attempts to clean up the mess.