Best Answer - Chosen by Voters
I'm studying O'Connor right now so I know the answer.
As background O'Connor wrote during the contemporary period which focuses on irony, destruction, dysfunction, sex, profanity, hypocrisy, and clashes between two different groups (conservatives and liberals)
Basically he writes to show in a blunt way how people focus so much about themselves, or the corruption of society in way that we will all critique the person in the story, but in reality, it is reality. For example in a story I read. "A Good Man is Hard to Find" There is this lady who is so self-centered and only cares about herself, but when she is at gun point, she is all good and will change. This shows that when people are at gun point, we will be all good because we are being watched. But if we don't have a threat, we will act however we like.
So if you see a dysfunctional family and understand what is going on, and then you try to apply it to real life you see that it is a part of reality. O'Connor wants to show how corrupt society is, so people can see how they really act through someone else's eyes. That way they can hopefully reform.