Keep the core clean extensibility principle

A BAdI (Business Add-In) is an SAP enhancement framework mechanism that allows developers to inject custom business logic into standard SAP processes without modifying the original source code. Developers implement a BAdI to extend or check standard application behavior — for example, to validate a purchase requisition as part of a procurement workflow. BAdIs can also serve as a practical workaround strategy when a released SAP API is not available for a required extension scenario.