There are five categories of small-business work where AI substitution in 2026 costs more in trust and liability exposure than it saves in productivity: (1) signed legal documents and tax-return positions, (2) trust-laden customer touchpoints (cancellations, refunds, conflict de-escalation), (3) regulatory submissions where the human signature is the audit trail, (4) anything requiring genuine domain credentialing (medical advice, licensed financial advice, signed engineering work), and (5) the first six conversations with a new high-value client.

Status set to Partial at publication because category 5 (the six-conversation high-value-client window) is the only one of the five not anchored on a regulatory or licensing-board surface; the supporting evidence is operating-pattern observation plus general B2B trust-formation research, not a category-specific cited consequence. Categories 1-4 are anchored on cited court records, regulator alerts, FDA/FINRA/SEC/NCEES guidance, and customer-trust research.