Why people go for Post doc?

[flyinglion]

Well, just my curiosity, why people go for a post doc after PhD?

They cannot find a good job? They love someone's researches very much? Or to get some speific training that they cannot receive during grad school?...

[UnlikelyGrad]

It's very rare to get an academic job straight out of grad school, at least in the sciences. A post doc (or two) is pretty much mandatory if you want to be a professor at a Ph.D.-granting institution.

[socialpsych]

My impression is that it 1) is pretty much expected in some fields (as UnlikelyGrad said) and 2) helps you build a CV with a larger number of solid publications before looking for a TT job.

[Aceflyer]

In the sciences, doing a post-doc is almost as necessary as earning a Ph.D. Doing a post-doc seems to be less important in some engineering disciplines, though.

[alicealice]

If you get a tenure track position straight out of a PhD program then you'll generally have no choice but to continue the research you started in grad school. Postdoc positions give you the opportunity to change your research focus and to further distance yourself from your PhD supervisor's research agenda.

[thepoorstockinger]

Because when you get a teaching position you're often too busy to do as much research as you like. A post-doc allows you to spend pretty much all your time researching/writing before you

It also can offer you geographic opportunities you might not have if you're trying to do research at a place where you can get a teaching gig (i.e. access to certain apparatus or places to do field study in the sciences, archives in the humanities).

[twocosmicfish]

In the sciences, doing a post-doc is almost as necessary as earning a Ph.D. Doing a post-doc seems to be less important in some engineering disciplines, though.

I asked this question of an engineering professor (and potential advisor) - his response was that US citizens never do post-docs in engineering because there are too many good opportunities compared to the life of a post-doc. International engineering PhD's do post docs because (1) it lengthens their study in the US, (2) lets them have a more directive and supervisory role than they did as a grad student, and (3) gives them more to hang their hat on during faculty applications.

[Stories]

In the sciences, doing a post-doc is almost as necessary as earning a Ph.D.

This. Very few in sciences go straight into a tenure track position from grad school.