I have written on this topic before. I am returning to it because I have another idea. There are different situations which require different explanations.
Kittens at play
When kittens play with toys they seem to be preparing for an adult life of torturing prey. They pounce on their toy, fling it up into the air and leap after it or they flip it over their shoulder, spin around and trap it.
The kitten is practicing three distinct killing methods. In the first the prey is a mouse, the second is an act of practicing catching a bird and the third is the final killing strike for catching fish.
Adults cats seem to be doing something similar when they attack prey. This feline behaviour is considered to be a despicable act of torture by the cuddly family cat. It is a much criticised aspect of cat behaviour but it is not an act of torture. Cats don’t have the faintest idea what torture is as it is a human creation.
When adult cats appear to be torturing prey by playing with the poor, barely alive or profoundly dead creature – often a mouse – they are acting out their powerful hunting urge despite being well fed and therefore in no mood to eat. The cat is not hungry enough to start feeding and so acts out her hunting rituals to pounce and pause over and over.
There is a third scenario for experienced set-feral and feral cat hunters or wild cats. These cats are hungry enough to kill and eat promptly but don’t do so because they are being cautious due a fear of suffering an injury such as a nasty bite from a rat. They prefer to swipe at the prey again and again until they feel it is safe to grab the prey in their teeth.
A fourth possible situation explaining why domestic cats appear to torture prey is when a mother cat half kills a mouse and brings it back to the den for her kittens to finish off the job as a lesson in killing.
This act of killing about which many people are rightly squeamish is entirely natural for the cat. It is a pleasure for them. If they were humans we’d label them psychopaths but that concept too is entirely human.
As feline ‘torture’ is considered bad cat behavior, below are some links to more bad cat behavior. Note: feline behavior is never bad in an absolute sense. It is only perceived as bad by humans.