Archive.Today was born precisely out of an understanding of the fragility of services from which it itself is not immune. And this is not a project to transmit information to distant descendants, it is a project to let latecomers be witnesses. Having the magic to assure continuity, I wouldn’t need to invent such weak tools.

—The anonymous operator of Archive.is, on their Tumblr

Emphasis mine. Fascinatingly pragmatic view of the short-lived nature of any human project.