Connecting logins insures that your access to Dapps can all be managed under one account.
When you connect your other logins to your ORE ID account, you'll be able to manage your access to any other ORE ID enabled Dapp all under the same account for the social logins you have connected.
For example, if you created your ORE ID account using a Facebook Login, and later you connect Google and Twitter, you can log into new Dapp using any of the 3 logins, all managed under the same ORE ID account.