I was never chosen and at the time I was quite annoyed about it.
Academically I was always top of the class, or joint top with my friend. She was made a prefect in final year. I was not. The differences between us:-
She was also sporty and on the school netball/hockey teams
Her parents were well off and was always beautifully turned out.
I on the other hand hated sport and did everything I could to avoid it. I never looked "tidy" because my uniforms were second hand from the Liverpool "Paddies market".
I used to imagine that her success in being selected a prefect was because she was more of an all rounder and her immaculate appearance.
I now recognise that it was probably more a matter of attitude. I always had a somewhat cavalier approach to the school rules. I got off with a great deal because of my academic success and prowess in music and drama and my willingness to represent the house in competitions. I never turned up for detention, not once. I often answered back teachers in a way which appeared cheeky and entitled.
Prefects need to present themselves as a role model to other students. I never aspired to that but tended to plough my own furrow.
Were you ever a prefect or school captain? Did you aspire to the role or were you simply selected?