What're the most convincing UFO accounts you've read or heard of ; and how do you explain them ?

The O Hare UFO, sighted by many credible witnesses, about 15 years ago, is the most credible account I have ever heard of. Official Explanation- "weather phenomenon". 

Oh, okay.

There are things I've seen that I can't explain - and I've read accounts by people that may or may not have only been stories... so far, nothing has convinced me of visits to Earth by ETs. 

Nothing has convinced me that E.T. Exists.   Most UFO's are man made right here on Earth.

Giza Pyramids.

Not one single UFO account I have read or heard has been convincing or even remotely credible.

I have been involved with the ufo scene for half a century, and in all that time I have yet to come upon a "ufo account" that is anything more than some Earthly phenomenon, either natural or artificial.

Often the explanation is right there in the mind of the observer. The witness wants to believe in some sort of unearthly nonsense, so they either deliberately or subconsciously hype up whatever they saw.

IMAO the psychology of ufos is not given enough priority. Instead of first asking about the mind state of the witness and indeed the collective mindstate of contemporary western society in general, and working from there, the usual pattern is to jump strait to the ET hypothesis. This is summed up nicely by the principle so dearly held amongst the believers: "don't know what it is therefore it must be space boogiemen".

There are plenty of ufo encounters which convincingly indicate we are dealing with a primarily psychological phenomenon. A mass delusion basically. Any ufo "sighting" or encounter is easily and convincingly explained by the science of psychology. They have nothing to do with the physical sciences, and are certainly irrelevant to astronomy.