A site's structure, i.e.: the physical site, is not the totality of the infrastructure that is required to make the cloud work. There are other mechanisms which are required to be up all the time before the site's 99.99% uptime can be guaranteed. If a broadband provider's service goes down, the site's 99.99% uptime becomes completely irrelevant, and the user is left with no service, and it doesn't matter who is the culprit. If power goes out somewhere along the line and in-between the site and the end-user, then the uptime at the cloud provider, again, becomes irrelevant.

The cloud is much more than iCloud or Google or Microsoft. It's a whole bunch of intermediaries and steps which must be operational, and each must be truly 99.99% reliable before that 99.99% uptime for the cloud is credible.