"I believe the main reason why [Oppenheimer] failed [to be a great scientist] was a lack of Sitzfleisch. Sitzfleisch is a German word with no equivalent in English. The literal translation is 'Sitflesh.' It means the ability to sit still and work quietly. He could never sit still long enough to do a difficult calculation. His calculations were always done hastily and often full of mistakes. . . .
"In addition to his restlessness, Oppenheimer had another quality. . . . He always wanted to be at the center. This quality is good for soldiers and politicians but bad for original thinkers. He paid too much attention to famous people working on fashionable topics, while ignoring less famous people working away from the mainstream of science."
Freeman Dyson, "Oppenheimer: the shape of genius," New York review of books 60, no. 13 (August 15, 2013): 19 (18-19).