My cat has Hyperesthesia Syndrome and does this all the time. It's honestly more distressing for the cat than it is funny. I doubt all these cats in the video have it though.

https://www.petmd.com/cat/conditions/skin/feline-hyperesthesia-syndrome

[–] limelight79@lemm.ee 1 points 1 day ago

One of our cats had a serious medical issue (we think a tick bit her, but we don't know for sure), and after she recovered, she attacked her own tail one night. Woke up the next morning to find blood all over the house. Poor kitty ended up having part of her tail docked. :(