Why do dogs choose places to pee and poop?

Dogs choose places to urinate and poop because the place they are looking for is convenient for "communication" with the same kind. They can use excrement to communicate and transmit information through glandular secretion. Therefore, dogs will look for telephone poles, tree trunks, and wall corners when excreting outside. These are fixed buildings. Dogs excreting means expanding their territory. This is the nature of animals.