Business Partner and SCU in SAP EWM

Hello Guys,

In SCMB/SCUMAIN as well as BP, we are assigning the business partner roles and address, yeah for sure there are more settings in BP like identification , status and control.

Could you please let me know the reason why we need both SCU as well as BP.

I know SCU is the role that warehouse is acting ,in a EWM environment. But again here also we are assigning BP role as vendor or Customer.

In BP also we are assigning the BP role as Vendor or Customer.

Thanks in Advance.