Do you think aliens have landed on earth?

i believe that aliens do exist. but the idea of aliens traveling possibly billions of light years to get here only for them to crash when they enter earth (like that whistle blower said. according to him we not only have some of their space craft, but also alien biologics) just doesn't make sense.

i'm sure if aliens were looking to make contact with other planets, they could/would choose a planet that's more advanced with better inhabitants. compared to other lifeforms out there, i'm sure we look like dumb cavemen.