why do older grad students become bitter?

Lili:

The other day, a new grad student asked me this question. It brought me back to my own first year.

When I entered grad school, I noticed that the older grad students just seemed… oddly bitter? The 6th years were living in a different world from us 1st years. Some of them would joke about it, some would deflect when asked, and some students we only heard about. I always wondered what made them so. Does their love for science slowly leave as they pass their time here? Will I become that way?? How do I avoid that?

Well, it has been 5.5 years since entered grad school, so I feel I can answer that now.