I’m not sure what it could be, since I never get double inspected the same way twice in a row. I’ve had devices swabbed for chemicals, pat-downs, being made to walk through the metal detector multiple times (3+), and even standing still while a bomb-sniffing dog walked in circles round me.
Once when I was younger I was seperated from my family on Halloween. I panicked a bit and walked up the street towards where I thought they had gone. Then, I turned left, and came onto yet another street packed with Halloween celebrators. However, nobody was talking. I mean it was silent enough for me to hear my own footsteps and brushing past people in the crowd. For comparison, the other nearby streets were too loud to talk without shouting. I finally found the other members of my group after walking for a solid 5 minutes, and they all seemed to think I had never left.