Why is this? The upper layers of the hierarchy generate revenue; the archival layer is purely a cost. If the data are still generating revenue, at least one copy is on flash or hard disk. Even if there is a copy in the archive, that one isn't generating revenue. Facebook expects the typical reason for a read request for data from their Blu-Ray cold storage will be a subpoena. Important, but not a revenue generator. So archival media are a market where customers are reluctant to spend, because there is no return on the investment.
This means that both revenue and margins decrease down the hierarchy, and thus that R&D spending decreases down the hierarchy. R&D spending on a new archival medium is aimed at a market with low revenues and low margins. Not a good investment decision.
But that isn't the worst prospect facing a new archival medium. As we currently see with flash, R&D investment in storage media is focused at the top of the hierarchy, where the revenues and margins are best. The result is to push legacy media, currently hard disk, down the hierarchy. Thus new, archival-only media have to compete with legacy universal media being pushed down the stack. They face two major disadvantages:
- The legacy medium's investment in R&D and manufacturing capacity has been amortized at the higher levels of the hierarchy, whereas the new medium's R&D and manufacturing investments have to earn their whole return at the archival layer. So the legacy medium is likely to be cheaper.
- The legacy medium has latency and bandwidth suited to the higher layers of the hierarchy, albeit some time ago. It thus out-performs the new, archival-only medium.