Sometimes, willingness to change not just institutions but geographical regions — and drastically so — at each career stage seems to be taken as an indication of greater “commitment” to science and to the scientific life. And the only interpretation of this fact that makes much sense to me is that commitment to science is, in these cases, being judged on the basis of one’s willingness to throw all non-career-centered considerations to the wind:

“See how much s/he loves science? No partner who wasn’t willing to act as a scientist’s helpmeet would follow that pathway, shifting hundreds or thousands of miles every few years. The only roots this candidate has put down are roots to this scientific field. Clearly, with what grad stipends and postdocs pay, it’s not like s/he could have purchased a home anyway, even if s/he wasn’t ready to pack up and follow the siren song of science to the ends of the earth. We don’t have to worry that this candidate will ever leave us because of a partner’s career, or family responsibilities, or to surf — see how much already has been sacrificed to the dream of being a scientist!”

Pack your bags: assessing young scientists’ commitment to science. : Adventures in Ethics and Science