Hello li_shouheng,
Welcome to the Microsoft Q&A and thank you for posting your questions here.
I understand that you would like to clarify about the diffenrent options when make a RecoveryServicesVault between Owner and Contributor.
The difference in options when creating a Recovery Services Vault based on your role is due to Azure's Role-Based Access Control (RBAC). Azure RBAC provides fine-grained access management for Azure resources, allowing you to assign specific permissions to users based on their roles. - https://learn.microsoft.com/en-us/azure/backup/backup-azure-recovery-services-vault-overview
When your account has the Owner role, you have full access to all resources, including the ability to manage access permissions. This means you can see and configure all available options for the Recovery Services Vault. Owner role can perform functions or tasks without Contributor's role.
When you add the Contributor role to the same account, the permissions are more limited. The Contributor role allows you to create and manage resources but does not grant access to manage access permissions. This restriction can result in different options being visible or available when creating or configuring the Recovery Services Vault.
Owner might not be responsible for creating and managing resources than granting permissions to other users.
I hope this is helpful! Do not hesitate to let me know if you have any other questions.
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