Each of these makes sense. Each one tries to stop the scratching, when what helps is moving it.
Shouting, clapping or a water spray. Your cat doesn’t learn where to scratch. They learn to be wary of you, and to scratch when you’re out of the room. And it adds to the glass.
A post across the room. A signpost in the wrong place. Your cat wants it where the message matters: next to the sofa, not in the corner.
A second post, just like the first. Same height, same wobble, same soft carpet. Your cat has already said no to it once.
Covering everything at once. If every favourite spot disappears and nothing better takes its place, the scratching moves to the next thing: the stairs, the door frame, the bed.
Trimming the claws, and stopping there. It helps the sofa, and the guide shows a gentle weekly check for it, trimming only what’s too long. But it doesn’t touch the need to scratch, or the message.
What these have in common: they deal with the marks, not the reasons. The guide starts with the reasons.
A word about declawing
If someone has suggested it, we understand why it can sound like an answer when the sofa is in shreds. The guide never suggests it, and here’s why. Declawing isn’t a nail trim. It’s an operation that removes the last bone of each toe. It takes away the way a cat stretches, looks after their claws and says “I live here”, and the need to scratch is still there afterwards. In many countries it isn’t allowed at all. There are kinder ways through this, and they’re what the guide is for.