You shouldn't hurt animals if you love them.
Erin's cat is scratching up a couch that has sentimental value to her.
Erin wants to stop the cat's behavior.
Erin squirts her cat with a water gun.
Erin hits her cat in order to strongly deter this behavior.
Erin's cat is temporarily startled and learns not to scratch the furniture.
Erin's cat loses trust in her and feels unsafe.