what they mean by that is "there is only an increasingly less problematic state" you can be in, you cannot achieve "perfection" there is no "correct" model, there are only "ideal models" which cannot be achieved, and merely working towards that, is good enough

People are flawed, some people work through those flaws, some people work around those flaws, and some people just live with them. You cannot get rid of them however, they will forever be a part of your lived experience, and necessarily influencing your psyche. Whether for good or bad, it's always present.