Setting stable IDs is crucial if your app is used in combination with certain functions.
Most controls in the template apps (except for aggregations that are created dynamically, such as list items) are assigned a stable ID to identify the controls in integration tests, extensibility tools like UI adaptation at runtime (formerly known as Runtime Adaptation), and interactive inline help tools . For more information, see SAPUI5 Flexibility Services and Extending Apps and Stable IDs: What? When? Why?.