The worst criticism I ever received happened when I was an undergrad. I was under the mentorship of an extremely bright and competent biochemist, who today I could honestly say nothing but wonderful things about. I was being trained by her in basic molecular biology and biochemical techniques that summer, but unfortunately, right in the middle of my fellowship there, my relationship of 4 years dissolved (in a particularly nasty way). I was devastated, and left only barely functional, but thought it would be unprofessional and tacky to bring this up as an excuse for my despondence and inability to focus. I knew it was affecting my work, I just didn’t know how to broach the topic without sounding whiny and weak. Which, of course, made me more depressed.
I started making small errors in lab: forgetting to label eppendorfs, or to write down concentrations, or “over-clocking” the Pippettman so that chemicals got inside it. Stupid little things. But, eventually they reached a boiling point to Dr. Biochem, and she just snapped. She took me outside the lab, and just let me have it. The end was of the “You better re-think a career in science altogether” ilk, and she said she wanted to terminate my fellowship. I listened, and then it was like I just broke in half. All the pent-up feelings I was having about the breakup just came right out, and through my teary-eyes pretty much just begged her to give me a second chance. I can’t remember if I told her why I had been acting so spacey or not, but it must have been quite obvious to her that I was under some serious stress. I still get that humiliating feeling just thinking about bawling in front of a professor. It was mortifying.
However, happy ending. She agreed to give me another chance, and I resolved not to make her sorry. Over the next few weeks and months, I saw her opinion of me change. By the time I had to ask for letters of recommendation for grad school, I only felt the tiniest amount of apprehension about what her’s said (they are confidential). Of course, she was my thesis mentor, so I sent them out along with all my other letters. During an interview, a member of the admissions committee termed her recommendation “glowing.” I almost cried again right there (of course I didn’t), because only then did I realize how much her opinion meant to me.