Merge pull request #102443 from omidm1/patch-48

clarification of MSI usage

Author: PRMerger6

articles/hdinsight/hdinsight-managed-identities.md

@@ -14,7 +14,7 @@ ms.date: 11/20/2019
 
 A managed identity is an identity registered in Azure Active Directory (Azure AD) whose credentials are managed by Azure. With managed identities, you don't need to register service principals in Azure AD, or maintain credentials such as certificates.
 
-Managed identities can be used in Azure HDInsight to allow your clusters to access Azure AD domain services, access Azure Key Vault, or access files in Azure Data Lake Storage Gen2.
+Managed identities are used in Azure HDInsight to access Azure AD domain services or access files in Azure Data Lake Storage Gen2 when needed.
 
 There are two types of managed identities: user-assigned and system-assigned. Azure HDInsight uses user-assigned managed identities. A user-assigned managed identity is created as a standalone Azure resource, which you can then assign to one or more Azure service instances. In contrast, a system-assigned managed identity is created in Azure AD and then enabled directly on a particular Azure service instance automatically. The life of that system-assigned managed identity is then tied to the life of the service instance that it's enabled on.