It never ceases to amaze me just how many people feel the need to carve their initials, or a slogan, into plants, particularly cacti. Not just in the wild, but also in botanical gardens.
This was one of several defaced specimens in the Almuñecar Cactus Garden.
Even wall plants are not immune to being tampered with, this one being transformed into a smiley face. Also in a botanical garden.