When Windows 8 detects a network based on the assigned IP address, netmask, default gateway, etc., it remembers the network along with the setting you give it as a public or private network. If you change the configuration of a network (e.g. reconfigure your router), Windows may determine you are on a new network and assign it a name of Network 2 or YourAPN 2.
This less-than-friendly name shows up in many places in the Windows 8 UI, but unlike the good old days of Windows 7, there doesn't appear to be any UI to merge or delete these networks. What's the best way to merge or delete networks you don't want?