Adding friction has a real cost when the request is genuinely urgent and legitimate, which is why the guardrails matter as much as the fraud numbers. Any voice or behavioral data collected on executives needs clear governance and retention limits before this ever rolls out. This system raises the bar significantly, but it doesn't make impersonation fraud impossible, and it has to be pitched to leadership as risk reduction, not risk elimination. The callback and live-challenge steps only work if the registered contact channels stay current, so stale data quietly reopens the exact gap this is meant to close. And once this kind of defense becomes standard, attackers will start adapting their scripts to get around known challenge patterns, so the model and its challenge library need an ongoing review, not a one-time build.