A childhood belief about cats and dogs

This isn’t really my own belief per se, but something I recall from my childhood that was believed to be useful. When I was little, I noticed my mum had taken an empty carbonated drink bottle (unlabelled), filled it with at least 3/4 water & laid it down sideways on the soil of the flowerbed in our garden. I asked why she did that & she told me it was supposed to scare cats away, so they wouldn’t pee/poop in our garden (or at least that part of the garden). Apparently they’d see their reflection in the water & get spooked away? I don’t know, it sounded pretty dumb to me, but I never actually saw a cat react to it, so I still don’t know if it worked or not, LOL. My mum certainly believed in it, though & I think one of my aunts tried the same trick, so it must’ve been a thing back then (this would’ve been in the 1990’s). Sounds kinda silly, doesn’t it? 🤣