I don't care

When I was younger and even more recently now, when I got into fights or arguments and my mother would intervene to punish me, I would protest saying something to the effect of "But you don't know how hard I was working to NOT be as rude as I was! Can't you at least cut me a little slack because I could have been a lot more mean?"
She'd say "I don't care how mean you could have been. I don't care how much you tried to not be rude, you were extremely out of line" and proceed to dole out correction.
Her answer always made me angry and I never did quite understand it.
Til this morning on my way to school. All of the sudden I went "duh. Ahha!"
I really don't care how mean you could have been, you still were cruel.
That's exactly what she meant. And now I get it :)
I walked to school today. It is too lovely of a day to want to drive. Plus I'm doing my part to 'save the environment', the school is only 15 minutes walking distance away from my house, I need the exercise, the list goes on. And so does life.