It usually implies even greater self-praise:
Norman Mailer…ruminated on his failure to win the Nobel Prize.
politics that soured his chances, he declared; it was stabbing his
second wife with a pen knife in 1960. "The Swedes are very intelligent
people and they’re proud of their prize, and they’re damned if they
want to give their prize to a guy who is a wife stabber and as sour and
bitter as I am, and I don’t think I can blame them," he said.
I believe that Mailer has become a quite underrated writer, especially his Harlot’s Ghost. But wife-stabbing is not the main reason why he has failed to win the prize.
Here is the link and article, which focuses on Gunther Grass, another tricky self-deprecator.