I believe it and in the case of the towers in NY, people react differently under stress and in media interviews than they might otherwise.
A couple of stories.
When I was with the police we had a stake out for armed robberies at a small late opening grocery store with two plain clothes police parked facing the front of the store both with front seat views from their car of both the store entrance and the cashier. The store was opposite side of the street to them on a T intersection so the unmarked police car was 50 yards or so away.
These two police who were known by their Sergeant to be very unhappy to be doing stake out duties sat there as two gun men robbed the store and left. Their first clue to the robbery was the alarm bell over the police radio with the call of an armed robbery at their target store.
Their Sergeant wanted them charged internally for a disciplinary breach as that is how they deal with screw ups in that force.
Their version of the story got them off the hook but just barely.
They said they saw these two guys enter the store who looked like f..k rats (the term of the day back in the 70s) and then a few minutes later they saw them at the check out with some stuff they assumed was being bought. They thought the money they were handed was change. They did not see a weapon nor did these two bad guys run from the scene. Their vision was limited to what they could see between the buildings which was about 3 or 4 store fronts one of which was the Chinese grocer. At this point of the story, they'd have not got off without a disciplinary note to file or even a day or two suspension but for what happened next.
The Chinese grocer then checked out several more customers right after the robbery and then they saw him pick up the phone where moments later they realized that that was the call in to the police about the robbery! The grocer did not bother to do what police advised all these merchants which was to report direction of travel as he was too busy checking out the groceries for the following customers! He did not look out the door to see where they went.
This was not uncommon when small store owners got robbed in those days as the call would be broad cast too late for setting up quadrants as these mostly Chinese mom and pop store owners would finish up with the customers in the line before calling it in. In fact, that is why his Sergeant went to stakeouts as these two unknown then but caught later robbers were working the area pretty well and we have 140 plus small shops open late at night over a quarter of the city and had to have better tactics.
Our stakeouts were not similar to what I heard about at an FBI training session for our force. They told the story of one guy who kept volunteering for stake out duty which meant he'd sit in the back room or behind false fronts with a shot gun. For some reason every stakeout he did was ending up with the robbers dead. The funny was he shot two robbers with shot gun blasts but both this time they didn't die. The cop took the stand and said he called out "police officer. Drop your weapons". He said they didn't so he shot them both. The bad guys took the stand and their lawyer asked if they heard this command. Both said all they heard before they were shot was "Take this you mutherf..kers." His force then understood why he was keen to work stake outs when everyone hated it.