The common sense reason why some domestic cats don’t purr is because they just don’t. It will be rare but it is distinctly possible. Feline purring is not an automatic or 100% guaranteed behavioural trait.
THERE ARE SOME PAGES ON CAT PURRING BELOW THIS POST….
Some cats don’t meow or they hardly meow. I have a visiting cat who has never meowed but she trills all the time. It’s strange until your remind yourself that cats are individuals with their own characters like people.
Some cats meow incredibly silently or deliver a completely silent meow. A lot of cats do. The British Shorthair purebred cat is predisposed to this in my experience.
If you think that your cat does not purr you may be mistaken as she may purr but very silently. You can check by gently placing your hand on your cat’s throat to feel the physical movements. You might not hear anything but there will be purring movements – vibrations – in the voice box.
There is a potential health issue here too. Perhaps there may be a problem with the cat’s voice box. The vocal cords may be injured or infected. Health problems need to be ruled out before you can address possible personality traits.
The standard sounds that domestic cats make are infinitely modified and varied by individuals.
Purring is a signal that a cat is content, primarily, but it is a sound that is made when a cat is in need of comfort too. It has a variety of meanings.
Bearing this in mind there is one last reason: a cat who does not purr might be permanently discontented. It is possible although unlikely. Perhaps a very stressful environment might lead to a cat being almost silent. Combine the anxiety with a chronic illness and you could well have a cat that does not purr.
SOME MORE ON PURRING: