Sometimes your cat is misbehaving and you want them to stop. Yelling at them is not the proper way to talk to them. You have to say it in a normal tone. If you say it in a loud voice you will frighten them and if you say it in a soft tone he will think he is doing something right. Normal tone is the way to stop a problem because it is not to high and not to low. It tell the cat he should stop what he is doing. It is hard to realize that your cat is being bad when you first get him but you have to understand he is just a cat and doesn't know better.