This was a couple of years ago, but I remember using ChatGPT to try and study for a certification by generating quiz questions.

It would always start to make every correct answer option "C" over time, no matter what I tried. Eventually I was so focused on whether or not it was stuck in a "C" loop that I started overthinking all of the questions and wasting time.

Flash forward to testing Sonnet 4.6 recently to try and see if it could effectively teach me something new, I got about 5 prompts in before I had to point out an oversight, and it gave me the classic "you're absolutely right, ignore that suggestion".

This is anecdotal of course, but at least LLMs are helping to build my skills of fact verification and citation checking!