Availability Heuristic
Also known as: Availability Cascade, Echo Chamber, Bandwagon Effect
We tend to believe or provide weight only to the things we can remember or think of in the moment. We don’t put as much emphasis on the possibility that there is other evidence we just can’t recall or don’t know about yet. We are naturally limited by our life experience.
There is also an “availability cascade” is when an idea becomes available, so people start talking about, which leads it to be more available, and thus talked about more. It “echos” around, making people think it’s more correct than it might be.
Examples
We tend to prepare for the last disaster, because it’s the thing we can remember. So we’re over-prepared for what has just happened, and under-prepared for what might happen next, since disasters often do not repeat. See: Stop Preparing For The Last Disaster
In politics, it’s become well-known that if you repeat something long enough in enough channels, people will simple believe it, because “everyone says so.”