The skills you need to acquire to build the infrastructure ten years ahead of the market’s demand for it may have zero intersection with the skills in demand in the commercial world. Not only are you not prepared to be a winner, you may not even be prepared to be basically employable. You leave and start again at the bottom. Worse than the bottom: you may have been trained with habits commercial entities find objectionable (like a visceral unwillingness to push pointers quickly, or a regrettable tendency to fight with the boss before the interview process is even over.) This can be fantastically traumatic.
Damn, that explains a lot.