Why would Android display "Security policy prevents use of unsecure networks" message?

When ***disconnecting*** a non-rooted stock Samsung Android Nougat (7.0) device from a WPA2 WiFi connection, Android briefly displayed the following message: > Security policy prevents use of unsecure networks. An internet search found a thread with someone reporting the same issue , but no resolution was provided. Why would Android (or perhaps something in Samsung's ROM?) be presenting this message?