Shows how different the software ecosystem is. For a product that I worked on - during a decade, the DB system got swapped out 4 times - all driven by customer

Shows how different the software ecosystem is. For a product that I worked on - during a decade, the DB system got swapped out 4 times - all driven by customer demand. The app software evolved continuously but the DB was hard changed - with all relevant schema and data migration applied during the upgrade process.