Well, that doesn't sound suspicious at all.

I'm pretty sure UFOs are just us in the far future, building saucer-shaped time machines to travel back in time to warn us now people.

Unfortunately, due to massive future deregulation of safety requirements, plus massive funding cuts to pilot training, navigation, math, and science in general, the future-us time-travelling "aliens" are not able to safely land or even fly their craft.

That's my theory, anyway.

Pffft. Reality isn't worth the paper it's printed on.