It's called "confidence." When I went through the confidence course at Lackland AFB (aka "Obstacle Course"), I was with a flight of officer candidates from ROTC units. We were all about 20-21, rising juniors in college.
We ran the course with a couple of flights of BMT's (Basic Military Trainees) -- new recruits mostly out of high school. One of our female cadets climbed the 30ft tower made of telephone poles spaced horizontally about 4 ft apart. You had to go on the outside of a pole, then the inside of the next, as you climbed to the platform at the top, then use a rope to climb down the other side. She was all of 5-feet-nothing and 105 lbs. This young guy next to me was watching her climb. He had to be 6'2" and 170 lbs. As he stared up while she climbed like a monkey, I heard him say, "I can't do that!"
Nothing on the course was overly tough, but each one had specific rules to make you follow directions. No ingenuity/cheating allowed!
What I saw in the video was someone lacking confidence - afraid of making a mistake, and giggling from nerves. She appears to have been taught she doesn't have to do anything she isn't comfortable with. I see it all the time. Hopefully the trainers will build her confidence through repetition and patience. I've seen good people wash out of basic just because they couldn't handle being told they are doing something wrong every 10 minutes. That's part of the training. I would rather someone wash out under artificial pressure than when the S#!% hits the fan!
Just my unprofessional opinion!!

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