IMHO, because we live in one material universe of an 8 or 12 fold CP symmetrical copy multiverse.
As a consequence everything is-, even humans are instantaneous entangled with 7 or 11 copies of ourselves.
To find out we need to extend a simple experiment already done by B.Libet in 1964.
Benjamin Libet measured the so called electric Readiness Potential (RP) time to perform a volitional act, in the brains of his students and the time of conscious awareness (TCA) of that act, which appeared to come 500 m.sec behind the RP.
The “volitional act” was in principle based on the free choice to press an electric switch button.
The results of this experiment gives still an ongoing debate in the broad layers of the scientific community, because the results are still (also in recent experiments) in firm contrast with the expected idea of Free Will and causality.
However I would propose the absurd but constructive possibility that we are not alone for decision making in a multiverse as an individual person.
see: Democratic Free Will and Telepathy in the Instant Entangled Multiverse.
One of the Copenhagen interpretations of human observation influencing wavefunction collapses.
E.g. for human observation of dead or alive Cats in boxes.
According to Quantum FFF Theory however, humans are not supposed to kill cats in boxes only by observation.
The alternative Quantum Function Follows Form Model interpretation of (Charge Parity (CP) symmetric) instant entanglement based collapse between multiple universes.
E.g. NO human influence on dead or alive cats in boxes.
Mirror symmetry between CP symmetric entangled multi-universes, means, that all wavefunction collapses are entangled between (anti-) copy wavefunctions.