That's because eye witnesses are quite often wrong. Case in point, AA587 which crashed in Rockaway (Queens, NY). There were some people who clearly stated, on camera, that they saw a missile hit it. Didn't happen. Pilot error (actually due to incorrect training) caused the Vstab to get ripped from the plane.
“That’s because eye witnesses are quite often wrong. “
Eyewitnesses are most often accurate enough so that our legal system functions by use of witnesses testifying in courthouses throughout the country every day. The vehicle of cross-examination can be used to point out discrepancies or mistakes in testimony, but taking a broadbrush and discounting the value of eyewitness testimony to any event is foolhardy.