Some just sleep in dirt, having burrowed a hole to provide some comfort. Or must stay on the hard concrete of the driveway, staring at the green lawn. Their water freezes, they bowls are turned over and left empty. They have little contact, human or animal. At the end of a rope nice dogs turn into barkers, which make people shun them every more.
Few people realize a barking dog is a lonely animal trying to communicate the one way it has left.
More than anything dogs like to shit away from where they eat, sleep and hang out. The dogs who live life on the end of a rope often have to stand in their own urine and shit, like a medieval prison. S ure, I know there are laws about dogs running loose, and I realize that not all dogs will stay around a yard. If a dog is tied up outside for reasonable intervals, it can be enjoyable. At least they can watch the action to pass the time.