Imagine that you're moving 200 personnel on a flight. Amongst the passengers are:
1 x Brigadier, who has been in the Army for 28 years.
4 x Lt Cols, with more than a hundred years service between them.
13 x Majors, ranging from young thrusters to crusty old farts, but all of whom know what they're doing.
16 x Captains, desperately trying to impress all of the above.
1 x female Second Lieutenant who has been commissioned for three months.
2 x WO1s.
9 x WO2s.
Multiple assorted SNCOs.
Guess which one is appointed the Chalk Commander?
Correct, it's the 21 year old female Second Lieutenant who is so nervous she's still calling Captains 'Sir' and is now faced with the task of marshalling an entirely recalcitrant mob onto an aircraft whose crew are engrossed in playing The movements game.