Speed and cross-functional coordination are the defining requirements. A realistic workflow: hours 1–2, initial legal and compliance assessment of the update; hours 3–5, legal review and sanctions list reconciliation; by midday, system and screening filter updates; by end of day, counterparty communications and internal certification. Any firm that cannot execute this sequence risks two outcomes: blocking legitimate payments (operational cost) or processing a sanctioned transaction (regulatory and reputational catastrophe).