Although i belive in life on some other pat of the universe .. but still UFO is some topic which i doubted the most.
One of the reason is most of the sightings are in developed countries like uk, usa which had been active in war planes development and one very common answer to UFO is new planes tested by airforce. Definately if some1 finds a blackbird plane in air before it was actually made open to public, he can certainly point it as UFO.
There might be a possiblity that some of these sightings were genuine but the genuinty of UFO over all is deminished by we humans only who just report false sightins to gain fame
the same held true for crop circles and i think these false statements are the main culprit because of which its still a mystery.
In the end
its matrix again ... and nobody is neo