@bopambo, I was admitted to the best PhD program in the world in a STEM field.
I had worked very hard on my undergraduate thesis. I took on a problem that others had started but not finished and worked intensely (while playing a minor varsity sport and doing well in my classes). Apparently, I did very well on this. So far so good. My work on this helped me get great offers from the five best graduate programs in the country (and I think the world, but who knows).
But I was just exhausted and didn’t feel like starting grad school. I didn’t realize I could defer. So I went and had a lackluster year. Did fine but didn’t really have the energy. I also felt the department’s focus was more theoretical and my interest was in having an effect on the world. So, I dropped out at the end of the year and took a job.
The good news @bopambo is that I reapplied while on the job to the department with my advisor’s collaborator. All the schools had offered me full rides with no teaching or research obligations the first time. The second time around, they just gave me the same offer.)
In the second grad school, they gave me tremendous freedom to take courses from other departments and professional schools. I realized that I really wasn’t interested in working in the field in which I was getting my PhD, but did begin work in a new, interdisciplinary field as a grad student in which I have worked since then.
What to do? Drop out and start again? I decided that the best thing I could do was get my PhD in this STEM field from a prestigious university, and that this would help me later. People would say, “He must be smart if he got a PhD in a hard subject from a prestigious school.” But, it is difficult to generate the energy to write a doctoral thesis in a subject you are not passionate about.
I did go see a therapist and got one of the early proponents of cognitive behavioral therapy to work with me, which was a powerful experience. I gritted my teeth and pushed through. It was hard. Took me 4.5 years total to get my PhD (1 at the first school. 3.5 at the second). I think without the confusion about my interests I might have done it in six months or a year less.
The good news is that it worked out well. I got a post-doc to work in a new field at a prestigious business school and used that to begin research in the new inter-disciplinary field. I then worked there as a junior professor and wrote my first book. After a few years, I decided to leave academia temporarily (and then permanently) but still have a minor appointment at the same university. I have had a fulfilling career running a consulting firm that I co-founded and helping people start other companies – sufficiently fulfilling that I do not have any desire to retire – and have done well enough financially. I do pro bono projects that feel meaningful: I helped end a civil war as a result of one project and created another that apparently was responsible for the passage of at least 13 bills in Congress (could be more because a major foundation has been funding an effort to institutionalize what I started}…
@Python20’s advice is good. I didn’t ask for a masters degree (or what it would take to get one). I did get it when I went back for my PhD but didn’t get any degrees from the first grad school. I would suggest to your son that he pay attention to the optics – what is the story he is going to tell folks when he applies for jobs or grad school. As long as he has a good spin, then he just needs to find something he loves to do and is good at (that the world also values). If grad school would help him get there, he can reapply. If not, no need to finish. But I would say it would a better story if he got a masters and then left.