Why do people think it is unlucky to pass someone on stairs?

Many people believe it's unlucky to pass someone on the stairs due to superstitions rooted in historical and cultural beliefs. One theory suggests that stairs symbolize a transition between different realms, making it inauspicious to cross paths, as it may disrupt the flow of energy. Additionally, some believe it can lead to conflict or bad luck, as sharing such a confined space can create tension. These ideas have been passed down through generations, contributing to the superstition.