It only appears rare for two reasons: the proposal consists of a literal fence, and we’ve no idea how many such failed or denied proposals have come before it.

It only appears rare for two reasons: the proposal consists of a literal fence, and we’ve no idea how many such failed or denied proposals have come before it. Surely it must be well-known that it is exceedingly rare, but valuable, for an organization to document why they didn’t do certain things.