Why Some Travelers Do It
The real reason for placing a cup or glass on the handle is not to physically stop anyone from entering. It is to create a sudden, unmistakable noise if the door moves. If someone tries to open the door, the cup falls, hits the floor, and makes a sound loud enough to wake you or at least grab your attention. That small moment can matter because it gives you a few extra seconds to react, turn on the light, call the front desk, or simply become aware that something is wrong.
That is why some travelers like the method. It is not a miracle security system and it is certainly not perfect, but it is cheap, fast, and requires almost no effort. In many cases, someone who quietly tests the door does not want attention. The last thing they want is a loud crash announcing their presence. Even if nothing ever happens, the setup can offer peace of mind. It is less about fear and more about removing uncertainty while you sleep in an unfamiliar place.
