Einstein’s Ph.D. dissertation was printed in Bern 30 April 1905. In 24 pages of calculations and text Einstein’s estimate of Avogadro’s number came out wrong by a factor of nearly 3, but good enough for a PhD degree in Mathematical Physics from Zurich University.
Realizing that the answer in his dissertation was wrong, Einstein made a correction for a magazine article the following year, after receiving help from Paul Drude the editor of Annalen der Physik. … After 18 pages of mathematics Einstein produced an estimate of Avogadro’s number wrong by a factor of nearly 1.5 on the second attempt. … A few years later Einstein’s estimate was found to be wrong in experimental work with chemical reactions, so a friend helped Einstein make another correction. … [N]ot bad for a third attempt.
Look! Even Einstein’s dissertation wasn’t perfect. Einstein, people.