The method itself is surprisingly simple. A water bottle is gently rolled under the bed shortly after entering the room. The intention isn’t to expect something unusual, but to quickly confirm that the space is open and unobstructed. If the bottle rolls smoothly from one side to the other, it usually indicates there’s nothing underneath. If it stops or changes direction, it may simply be bumping into stored items such as extra bedding, cleaning equipment, or misplaced luggage—things that can then be checked calmly and safely.
Why Some Travelers Place Water Bottles Under Hotel Beds
