The designer would / should have "tested" the design to
all of the datasheet electrical performance table line items.
This would / should populate a test requirements document
in an orderly product development flow. The TE would
develop the test platform implementation (and perhaps
supplemental resources, like bench jigs and support) with
the DE as a resource and the PE (product engineer) as the
"customer" (saying when complete and credible, etc.).
Over-the-transom verification and test development does
not often work well. The test engineer only knows what
to apply and expect, when someone or something tells
them. And chip designers may be insulated from "big
iron" tester, harness, load board practicalities requiring
some thought about methods, different than as-simulated.