Humans have a fascination with regularity and rhythm in nature, and find this comforting as their own bodies have such rhythms - in heartbeat, biorhythms, and sleep-wake cycles. The dance, repetitious motions during exercise, rocking the baby, and music all reflect man finding comfort in regularity and rhythm. Nature's patterns are everywhere, from the pedals of flowers evenly spaced in swirls to the intricate and balanced designs that snowflakes form. Thus it is that humans often seek regularity and rhythm in the midst of confusion, for comfort. The overwrought rock themselves, tap a pencil, or rub their chin. If the anxiety involves unknowns in the future, they may look for patterns by which to form predictions. Luck 7, 13 spells doom, he-loves-me-he-loves-me-not, and so forth.
There is no consistent number used in nature, nor is there any spiritual significance to numbers. Even we, the Service-to-Other Zetas, who are so often reported in groups of 3, do so only because we often work as peers, and without a leader a tie must be broken when instant decisions must be made out in the field where all votes are equal. Numerology seeks to comfort, to put unknowns into familiar categories, but numerology is without basis in fact. Those advocates who state otherwise, laying out patterns that fit the prediction, are screening what they see to fit the expectation. However, perhaps they are a bit less anxious.