Why an alien (extraterrestrial) culture might want to visit Earth
The Earth is inconsequential in the context of the galaxy and even more so in the totality of the Universe.
But if some alien visitation, years ago, came across this planet, they might have logged it in an intergalactic “directory” of strange “venues” containing life, much as Earth explorers have provided in the discovery charts of exotic places (here).
Madagascar is such a “venue” for example, or Hawaii, or New Zealand, to name a few.
If ultra-cultures have a co-operative library of unusual places where life exists in the Universe and the Earth has ended up in that library or directory, one might conjecture that space travelers would seek out the Earth because:
It contains an inordinate amount of water
It has a raft of exotic flora and fauna, which keeps changing (via evolution) over millennia.
This planet has elements that can cure illness: plants and flowers with medicinal properties not found elsewhere in the Universe.
One species of life on the planet, humans, offer examples of barbarism not seen in other intergalactic communities, behavior so bizarre as to bespeak a fluke of extreme nature.
Earth is a freak, among planets discovered so far. It is an outlandish outland which would cause interest among any thinking extraterrestrial species.
That UFOs are aloof derives from the hesitancy to disturb this specific environment for various reasons: contagion, a pristine (yet corrupt) existence that is unique among the planets of the Universe, or a fluke of ultra-nature that is grist for the curious among planet-roving civilizations.
We must admit that our Earth is odd in ways that would seem incomprehensible to an alien species, a species able to create ships that can traverse the regions of space, unencumbered by the petty or horrible strife that permeates our planet, a thoughtful curious species bedazzled by our strangeness, in behavior, environment, and configuration.
That UFOs comes in large numbers, with a variety of shapes and beings, gives a clue to the interest of other planetary visitors and the unique difference(s) that Earth showcases which attract inquisitive visitors from elsewhere.
Ancient astronauts don’t and haven’t come to Earth to help humankind. If they have come, they’ve done so for souvenirs or items and elements they need: water, minerals, life-forms (not humans).
If the Universe is one, in creation, thought, and mind, as Teilhard de Chardin posited in The Divine Milieu, The Phenomenon of Man, and other works, then the Earth has to be, by cogitation without bias, a quirk within the Universal milieu, something bordering on the insane.
Why wouldn’t that attract inquisitive extraterrestrials?