Different people need different amounts of sleep.
I know that when my mom made me got to bed a lot of the time I wasn't tired. I stayed awake for hours, and if I told my mother about that, she would just scold me for not falling asleep or trying to get to sleep. But I honest-to-goodness COULD NOT and I couldn't get it thru her head! She thought I was just being a brat but I wasn't trying to be stubborn at all! I did not find those things amusing! She would often stand outside my door too before she went to bed, to make sure I was totally quiet and once she imagined she heard whispering and told me off, but I hadn't made any sounds at all; my mouth was closed! She would tell me that I needed so many hours of sleep, but not everyone is the same, and anyway it wasn't like I didn't KNOW; it was a physical problem; you can't shame or talk someone into falling asleep if they just physically aren't tired!