Per https://docs.netapp.com/us-en/trident-2110/trident-use/ontap-nas-examples.html, the management LIF in question is the "IP address of a cluster or SVM management LIF". Cluster management is a separate IP space and has a separate volume (root volume) for it's purpose. It is kept separate from the data SVMs to keep ONTAP config and logs as well as ensure cluster stability. SVM management is less frequently used but can be used for things like VScan, FPolicy, etc.
Does this help?