Besides the people in this thread bemoaning the state of research funding, international students, etc. (all of which are valid), a lot of people are becoming disillusioned with academia. Probably 80% of the recent PhD grads I know are looking to leave academia, despite the fact that they went into it to pursue a career in academia. The median science PhD takes 6 years now, and is grueling work for terrible pay, all…
This is a timeless entry. It's aimed at humanities, but every STEMy person I have shown it to agrees with it.
TLDR: Only get a PhD under 2 conditions:
1 - You are rich and otherwise very bored.
2 - If by Christmas in your first year in grad school, you are absolutely certain that you and your PI get along so well that nothing could hold you back from carrying that coffin at their funeral.
If either condition is not met stringently, you're wasting yours and everyone else's time.