These pieces of advice are useful. However, they don't touch the bottleneck: mental health. And no, it is not "like any other demanding job". A PhD hits on two fronts - one is "all or nothing". If you spend years and still haven't submitted your dissertation, it is a career-ending failure. The other is its tie to one's identity. You put sweat, blood, and tears into your research, only to be rejected at a journal or conference because the result is "technically correct but not significant enough". Sure, there are similar parts in other careers - from talking with people, it works a bit similarly in medicine (when it comes to "all or nothing") and art (when it comes to this identity).
If people fail, it is mostly because they burn out. If they succeed, it is not unlikely that they will need to heal their burnout wounds anyway.
I am sure Karpathy's experience is different. But most people starting their PhDs are not Karpathy.
See also "The Lord of the Rings: an allegory of the PhD?" http://danny.oz.au/danny/humour/phd_lotr.html
Sure you may survive. But even if all goes well, you succeed, there will be a void in you after the quest.
If people fail, it is mostly because they burn out. If they succeed, it is not unlikely that they will need to heal their burnout wounds anyway.
I am sure Karpathy's experience is different. But most people starting their PhDs are not Karpathy.
See also "The Lord of the Rings: an allegory of the PhD?" http://danny.oz.au/danny/humour/phd_lotr.html
Sure you may survive. But even if all goes well, you succeed, there will be a void in you after the quest.