Why is actual correction so rare in the MSGK works?

I don't want the bratty girl to be dicked until she becomes a compliant/mindbroken cock sleeve. Because that way, she's still a brat, but now kept in check by fear or addiction to cock.
I want the bratty girl to be dicked until she genuinely reforms and becomes a far more pleasant person in general. But also still the cocksleeve of the one that corrected her.