What does Isaiah 64:6 mean?

We're all messed up—like something dirty that can't be cleaned. Even the good things we try to do are like filthy rags. We shrivel up like leaves in the fall, and our mistakes blow us away like the wind. Isaiah 64:6 - Modern Text Bible

(This verse admits that everyone is deeply flawed, and even our best efforts aren't enough to make us right. Our failures separate us from God, leaving us powerless.)