In Houston, Texas a businessman was able to sneak a gun in his laptop case while going through security at the airport. Security at the Houston airport did not detect the gun.Why situations like this happen?People unconsciously make a mental model of how often an event occurs.
The more often an event occurs the more people pay attention. If an
event rarely occurs people are more likely to miss it.When events are infrequent is important to use signs or any other clue so people can notice them.