Why does my dog shout when he hears the sound of collecting waste?

Why do you think your dog yells when he hears the sound of collecting waste products? Maybe some people collect waste products by imitating the sound of loud speakers, which makes the dog feel very upset, so he yells. Also, the car collecting waste products is noisy and noisy when it passes by, which is often said that dogs look down on people. If a dog sees a good or beautiful woman passing by, he will wag his tail and look at others with a smile. If he sees a garbage collector or a beggar, he will bark loudly. This phenomenon seems normal now. There are actually such dogs.