There's a belief that the planet Mercury being in retrograde causes all sorts of disruption to life on Earth. From astrology.com:

During Mercury retrograde, things typically do not go as planned: your airline ticket was never valid for travel, the oh-so-important meeting you cannot miss is rescheduled at last minute, your credit card disappears into the dark recesses of your local ATM. Communication, technology, and travel can be particularly chaotic, and it is not at all unusual for items to mysteriously go missing during Mercury retrograde.

IMO, the folk beliefs about full moons and Mercury retrograde are correct and observable in real life.