Sinning is in our DNA as in our bodies are corrupt. Everything about us, our thinking and how we treat each other, is simply not how God created us to operate. Our DNA is information of our makeup. We are essentially copies of our parents in a way, and if one believe in the literal Genesis, our information ultimately goes back to Adam and Eve. When they fell, it was like a virus entered in, a disease that began to tear at their bodies. We inherited this disease, just like sickle cell traits are passed down. That is why we can't be good, or you can say be perfect, because our makeup can no longer do what it could in the day of creation.
What is absolute good? Pretty much perfection. Having no evil. Yet we can just leave it at absolute good. We see good in relative ways, that's why people change over times, views change. Yet if there was an absolute good, if there was a level that did not change, that kind of good condemns us.
What is the physical process of this corruption you speak of? I am not certain I want to continue this dialogue under the assumption that a literal interpretation of the book of Genesis is anywhere close to possible or accurate.
What is this perfection? What is the state of having no evil in an absolute sense? It seems to me that evil is relative to what the society a human is born into thinks and is not innate to the human evidenced by the many regular cultural practices of humans throughout history that our society would label as evil.