Because we are so tech-centric, we forget that actually these scam tactics are old — predating even Internet scams — and very proven. ... They work with emotions. When they put us in the right mood and trigger anger or fear, we forget all the advice. In those cases, we lose common sense, and there's where [attackers] get us.
Link: DarkReading.com: Don't Answer the Phone: Inside a Real-Life Vishing Attack
Successful attackers focus on the psychological manipulation of human emotions, which is why anyone, even a tech-savvy person, can become a victim.
The old scams triggered greed to bypass our common sense. (Such as the Nigerian Prince). But fear is more powerful. If they can make you afraid, they can make you do what they want.