My understanding is that somebody decided that deleting requests is an audit issue that *EVERYBODY* needs to be concerned about (I think it should be configurable via administrative option... and I think the same thing for Approval Policies, which also cannot be deleted... even if never utilized).
You cannot Delete Successful or Failed Requests via the Delete button... the Delete button only works for "Unsubmitted" requests.
Any delete would have to happen through the backend data, I suspect.
