Axxman300
Philosopher
It's not so much that we can't believe what eye witnesses say they saw, it's their interpretation of what they saw that is unreliable. If they say they saw "a light in the sky moving at hypersonic speed", the hypersonic speed bit is an interpretation, not an observation, because they can have no idea how big and far away the source of the light was and hence cannot possibly estimate the speed. This is why the light from Venus being bounced around in the atmosphere and a firefly doing its mating flight can both be mistaken for aircraft sized objects a few thousand feet up doing physically impossible maneuvers.
Years ago on an early morning drive to work I saw the most spectacular thing in the southwestern sky. A white shimmering streak, miles long was stretching across the the Central Valley of California. It looked like the sky was being torn open. This lasted a few minutes and then quickly vanished (at least from my view).
Come to find out what I saw was the space shuttle, Discovery returning from orbit to Edwards AFB, 300 miles to the southeast of where I was, just north of Monterey. What I saw was the superheated shuttle flying through freezing air, heating water molecules briefly, and those molecules freezing into ice crystals. I just happened to be in the right place, with the rising sun at the perfect angle to make the ice crystals glow. As I drove south, the sun rose, and my angle of view shifted to make it all invisible again.
I'm not an expert on anything, but I'm a huge aviation buff. I used my knowledge to check the arrival time of Discovery at Edwards, and pieced the rest together. I have seen two UFOs, both long ago. One I think I can write off to a combination of three individual things happening at the same time and same place. The second one I still have no idea what it was, but it was huge.