Why can't you nail the door? Feng shui?

Hello, from the perspective of geomantic omen, water is wealth, aquatic wood, so wooden doors generally have the function of gathering wealth. If nails are nails and nails are gold, Jin Kemu will lead to financial ruin. In fact, there is no scientific basis for this. Now many villas are made of iron gates or stainless steel. I think you can't nail the door for the sake of beauty.