From Aldous Huxley's 1946 foreword to a reprint of Brave New World:
To pore over the [...] shortcomings of twenty years ago, to attempt to patch a faulty work into the perfection it missed at its first execution, to spend one's middle age in trying to mend the artistic sins committed and bequeathed by that different person who was onself in youth - all this is surely vain and futile.