I was thinking about how I'm not a fan of the image of mermaids constantly brushing their hair and looking in the mirror as it makes them seem shallow. But then I thought perhaps mermaids have to comb their hair out of the water because it's hard to do so underwater. Maybe they don't spend that much time brushing their hair but because it is one of the main reasons why they would surface humans are more likely to see them doing so and therefore associate mermaids with hair brushing. Perhaps because most mermen have short hair they don't need to spend as much time combing it so they spend less time out of the water, hence fewer merman sightings and fewer merman folktales.
Like I said a bit random but I had to share it. Am I the first to think this or not?