This is the most common answer I have heard from non-Christians in response to the question, “Why should God allow you into heaven?”
But this answer actually has its root in original sin.
After Adam and Eve rebelled against God, they experienced guilt and attempted to hide from Him. They also experienced shame, and so they attempted to cover themselves through their own effort. Once Adam and Eve became corrupt, they couldn’t produce anything better than themselves, i.e., all they could produce was corruption. Each one of us is born into this world as a little fallen Adam and Eve. And like Adam and Eve, fallen humankind today attempts to hide and cover from God. But rather than sew fig leaves together, one of the most prevalent ways we attempt to cover our moral shame and guilt is by appealing to our own moral “goodness.” That is, we point to our “basic human goodness” and “good deeds” in an attempt to justify ourselves before God. Often this even becomes a rationalization as to why we don’t need God, e.g., “Why do I need God? I’m living a good enough life on my own.”