I have proof: Amelia Earhart flew planes. She was a famous pilot. The aliens observed this. They realized that planes would eventually lead to more flight related inventions, and eventually would lead to rockets that could travel to the alien's planet/universe/anus. That made them realize that if this famous pilot suddenly disappeared, It would make all the humans scared that they would die while flying a plane. So then the aliens would not have to deal with these humans in the future. Discuss.