When an invalid resource is specified in data plane user's access policy ("grant access to") authentication errors are misleading.

For Example: if user "John" is limited access to cluster "xo" but cluster is created as "x0" by mistake, when John is authenticated against "x0" we simply get "user not found error" in client.

If the Atlas UI can highlight the potential error, that cluster "xo" is not found, as cluster cannot be implicitly created. it will save valuable time for developers debugging entitlement issues.