A reader is doubly guilty of bad manners against an author when he praises his second book at the expense of his first (or vice versa) and then expects the author to be grateful for what he has done.
ATTRIBUTION:
Friedrich Nietzsche (18441900), German philosopher, classical scholar, critic of culture. Friedrich Nietzsche, Sämtliche Werke: Kritische Studienausgabe, vol. 2, p. 433, eds. Giorgio Colli and Mazzino Montinari, Berlin, de Gruyter (1980). Mixed Opinions and Maxims, aphorism 130, Readers Bad Manners, (1879).