Why is the Project RBS automatically updated when creating resource assignment?

Summary:

Context / Configuration: A new Project ResourceBreakdown Structure (RBS) has been created, with Project Role and Named Personenabled as Resource Formats.

Observed Discrepancy: When creating a resourcerequest and resource assignment using a project role and named resource:

• In DEV5 (Correct/Expected Behavior): The resource name is not automatically added to the Project RBS.
• In DEV43 (Incorrect Behavior): The resource name is automatically added to the Project RBS.

Content (please ensure you mask any confidential information):

Question: Could you please explain why DEV43 isincorrectly adding the resource name automatically to the RBS? We need toensure DEV43 behaves like DEV5, where this automatic addition does not occur.