Folklore: Owls are often called "ugly birds" or "soul-chasing birds" because of their unique calls. In some areas, their calls are considered gloomy, sad and disturbing.
Scientific point of view: From a biological point of view, the owl's cry may be to find food, attract the opposite sex or serve as a symbol of territory. They do not portend human death or other disasters.
To sum up, the owl's cry at night can have different explanations, including but not limited to superstition, folklore and biological natural behavior. But these explanations have no scientific basis, and are more based on cultural traditions and personal beliefs.