The Security Retainer Shift: Why Proactive Threat Modeling Beats Reactive Cleanup

Security work is moving from one-off incident cleanup to recurring advisory retainers, because AI-generated code and autonomous agents have expanded the attack surface faster than client IT teams can staff for it. Agencies that bundle threat modeling, code scanning, and agent governance into a monthly line item capture margin that survives project churn; those that treat security as a favor lose the account the first time a leaked key produces a four-figure bill.