A minute in the product
Saving is not vouching. An administrator reads the question, the meaning, and the SQL.
Why the two origins matter
A formula-fact is true because the inputs exist here. A vouched fact is true because a person read the question, the meaning, and the SQL.
Without that second step every saved number drifts towards looking official, and the word trusted stops carrying information. A vouched-for fact teaches the system how your business asks its questions. It never answers on its own, because a fact confirmed in error would then be repeated identically forever, and the only way to notice would be for someone to read the query.
An evaluation copy is not an empty library. Standard formulas this warehouse can compute are already facts. An administrator has also vouched for a first set of saved answers, so the first session has facts to read rather than a blank tab.
Where to go next
Who enforces what: Trust and security. How a first session goes: How it works. Worked answers: Business questions.