I don't like them either. I find it hard to articulate why I don't like them. I definitely have experienced problems with them where they get into some state where the cell results are incorrect. Then, if I restart the kernel and run the cells again, I get the correct result. But I don't like them for reasons other than this one, and cannot explain why. I prefer the ipython REPL to the notebook.
Its a bit of nostalgia for me. It took a bit of work to understand ipython when I first started as a programmer, but that effort helped me in the long run. Using ipdb for breakpoints was a game changer in my first job.
And it also was a good way to get comfortable with using terminal.
Using notebooks removes all these learnings. I dislike it because it makes for less confident programmers in the long run.
