So everyone who has seen a UFO has not "seen" a UFO, but has "seen" something else?
Terry, I think Night Owl's question is warranted. You cannot, and I reapeat, cannot say that "everyone" who claims having seen a UFO has not seen a UFO. The mere name UFO implies that it is a flying object that cannot be identified. Implying that "always" when people see something that you do not believe in, or cannot understand or explain with what we already know from the world "at this point in time" is not what they saw, is simply a bit arrogant.
It is true that "mostly" when people refer to UFOs, they are thinking of alien crafts but that is not the case "always" if we go by what the acronym UFO stands for. I guess my point is that there are, in fact, objects in the sky that cannot be identified or, in other words, they cannot be paired with known objects that, according to our knowledge at this time, could be found flying in the sky. Now, if you are referring to the "interpretation" that this people give to what they saw, then you might have a point.
Here is one example of several people seeing something that they could not explain. What did they see? If you remove the interpretations, there is always the fact, that they saw what they saw, even on a radarscope, and could not explain it, therefore UFOs