If it cannot say I do not know
Then every number it hands you is unverified by definition.
When I do not know something, I say I do not know. I do not invent a number to fill a silence, so BLU does not either — and neither does the thing you are reading. If it is not fact, it does not get displayed as a KPI. No confident guess, no hallucinated number wearing a metric’s clothing.
That is the rule I would defend hardest.
WHY IT MATTERS
A number that was the exact opposite of the truth
Somebody on our team asked a general-purpose AI chat a question about our business that the underlying data could not actually support. It gave her a number. Not a hedge, not a maybe — a number. And it was the exact opposite of the truth. Not off by a margin. Inverted. It did that because an ungrounded chat has nowhere to put "I do not have this". There is no slot for absence, so it always has an answer, and the answer arrives in exactly the same confident voice as the true ones.
WHAT IT COSTS
Expensive, and kept anyway
The rule kills things I would like to be able to show you. I have kept it anyway, because a system that is right ninety percent of the time and will not tell you which ninety is worse than useless — you are back to checking all of them by hand, which is the job you were trying to stop doing.
A REFUSAL IS A WORK ITEM
Name what is missing and what would fix it
The morning report argues with itself and carries its caveats next to the number rather than in a footnote nobody reads. Zero Stripe charges behind this figure; a quiet day looks like this, and so does a stalled table. This figure is incomplete, not low. Five cancelled orders excluded. And when a credential dies: this is a refusal, not a zero, the figure is unknown rather than small, and the token has probably expired and has to be replaced by hand. A specific refusal is a work item. A vague one is an apology. I have never seen software I could buy behave that way, and I do not think that is an accident — a vendor has no incentive to build a product that tells you it does not know.