What is an upgrade or system upgrade?

To add to the discussion the reason I write articles about upgrading from something like Rock/4.3 to Rock/5.0 is because sometimes the upgrade is not as simple and straight forward and extra steps are needed. The article Upgrading Rock/4.3 to Rock/5.0 is a good example of an instance where extra steps are needed. These extra steps are essential to avoid problems. There is also an article in Resources forum regarding Upgrading from Rock/5.0 to ROME/rolling (2024-01-20). That one is more straight forward and simple at this time.