If the key must the same length as the message, and must be different for every message, I guess we can't really call that encryption. May as well communicate the complete message by which ever way the secret key was communicated.
It's a real encryption, much-much better than basically anything before because it's really unbreakable.
It's not useful or practical in many situations that we associate with cryptography over the internet, but it certainly has its applications.
Almost every other cryptographic scheme exists in order to increase convenience, at the expense of some security. The one time pad method is "perfectly" secure (assuming the key is securely generated, and kept safe), everything else is less than perfect (although computationally improbable).
For example, you generating a 1TB key before leaving on a trip you could imagine a VPN set up that encrypted 1TB of traffic in a way that was theoretically unbreakable by someone sniffing the traffic only.