Mentors who make it clear that they care deeply about whether their trainees “like” them should be considered highly suspect. You are not looking for a drinking buddy. You are looking for a mentor with two key qualities: (1) the ability to create an intellectual and physical infrastructure that will be sufficient to support your research and (2) sufficient attention and scientific judgment to guide you away from fruitless efforts and towards fruitful ones.
I hear stories all the time about “fun” labs where everyone is always dancing around to rocking tunes with the PI, but where no one’s projects ever pan out and students flee for other labs after two, three, or even four years.
Another big red flag is if in discussing projects with the PI, you get some really inspiring story about how X molecule, mechanism, or pathway is like totally the key to everything and we are just on the cusp of proving this totally awesome hypothesis and we are gonna be famous!!!11!!!eleventy and revolutionize our field. 99% likelihood is that you are dealing with someone who is *way* too enamored of their own ideas to be sufficiently critical to effectively guide trainees away from fruitless and towards fruitful efforts. This PI phenotype is frequently coupled with the “fun” lab one.
Don’t be fooled by this kind of shit. You want a lab with a good set of established methodological approaches and an interesting system within which to deploy those approaches.
Yeah, it’s great to have hypotheses so long as they are used to guide exploration. When someone talks in terms of “proving” a hypothesis that they consider “theirs”, run away.
(h/t Isis the Scientist.)