Somethings fishy with Earth
*season 6 spoiler in the VERY last line and is only a joke*
First when the galra took the Kerberos mission members they where relatively close to earth (in space terms), but then the Galra just ignore earth?
Then there’s the Terra shop in the space mall meaning that the greater space community KNOWS about earth, you can even GET things from earth. They seem to think of it as sort of an out of the way place thats more of an novelty than serious.
Conclusion: Galra know and have some kind of trade relationship with earth.
1) Earth has 0 quintessence and its really far away so the galra empire just dont care about it. Some individuals in the empire think they have neat stuff though!
2) Galras TRYED conquering earth, but earthlings are both tougher and crazier than they look (we literally have countrys that keep enough bomb to destroy the whole planet just in case another country decides to set off their world destroying bombs), so they gave up. Not wanting anyone to know of their failure the galra marked earth as a random easily forgettable planet out in the middle of nowhere.
3) option 1 or 2 happens then earth decides they want to open trade with the Galra, they say k. So galra gives earth advance tech (Keiths hover bike) and earth gives the Galra people (the Kerberos mission).
the Voltron teams gonna have a lot of fun on earth :)