[ovirt-users] what is "use host" field in storage domain creation??

hello and happy new year~ I am wondering the role of "use host" field in storage domain creation. https://www.ovirt.org/documentation/install-guide/chap-Configuring_Storage.h... above link says all communication to the storage domain is through "use host". but I can't understand inefficiently passing through that "use host" even though every host can directly access to all domains. it seems like i am misunderstanding something.