exTSRI

I suppose the professor-student dynamics are quite different in humanities vs. natural sciences. In the sciences, professors are the ones who get grants, even though students often participate in writing the applications. Professors come up with ideas for new research projects, but they completely rely on students and postdocs to do all the actual work in the lab, while they themselves assume the roles of overseers and managers (and are, in fact, commonly referred to as "supervisors").

@timuralp: True, it's especially critical before tenure. But for professors of any ambition, the career does not end with tenure. They still want to get things done and publish impressive papers, so that they can have better funding, a higher h-index and more awards than the other guy. So, unless they can somehow manage to do everything solo, a professor's academic success is always directly tied to his/her group. For students, it's not even always about needing a pep-talk per se. An extreme example, which isn't too extreme for the specific area of research and the level of competition: One professor used to give out faux medals ("purple hearts") to students who would work the day, the night, and the next day. Straight. That was a synthetic organic chemistry lab, so they routinely handled a lot of toxic and flammable/explosive stuff by themselves and around each other. Not a good mix with fatigue and sleep deprivation, if you ask me. I don't know if those students really needed the "medals" and the encouragement, or if they were insane enough to otherwise regularly do that on their own initiative. But, in any case, the prof had a rule: work 36 hours straight -> get a medal.

I agree, and that is an interesting point. I think it begs the question: if an advisor is investing in a student's career, what kind of returns on investment are they expecting down the road for themselves? In other words, why invest in somebody else's career? (Aside from being altruistic, but then it can't even be called an investment.) All the advisors I've had, including during course projects back in undergrad, readily expressed their desires for me to stand out, excel, "make a name for myself" and be very successful. And then went on to tell me that, in order for that to happen, I had to be working really hard, spending more time in the lab and so on. Which isn't exactly illogical, of course. But it makes you wonder. Is it really your future career (or, taking it up a level, happiness in life — unless someone has other reasons for wanting a good career) they are worried about, or is it mostly how much time and effort you put in while working for them and trying to go after that career?

What does your PhD advisor typically do or say to motivate you to work harder, longer hours, on weekends etc.? Because, of course, professors depend on their students and postdocs career-wise. And they tend to develop various management and motivation styles. Some flat-out demand ("my way or the highway"), others try to inspire. Some make you punch in and punch out, others don't. Some stress teamwork, others encourage internal competition. And so on. What's your prof like? My former advisor (Dr. M. Reza Ghadiri, The Scripps Research Institute, California, chemistry/biochemistry) called himself "a cheerleader". I'm writing a memoir-like post about it, you can check it out.