Cats love to scratch, and they scratch for many different reasons:
It helps to condition and sharpen their claws.
It’s a way of stretching their body.
It’s a way they can play.
Some cats use it to mark their territory.
The best way to avoid cats scratching your furniture is to have a scratch board or scratch post in place. Create a habit by spraying the scratch post or scratch pad with catnip spray to get your cat hooked. Spray every fifteen minutes for an hour if you are trying to get your cat addicted to a new scratch board or post, they will go crazy for it and then only want to scratch the scratch post – hopefully.
If after getting a scratch pad your cat keeps moving back to your furniture...