I suspect that anyone world class in any endeavor has had to give up his/her personal life to focus on one topic to master. To most people the cost is too high for the benefit of merely having someone bestow a "GM" in front of your name.
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(p. 75)
Larry Evans says the thing that makes Fischer
different from all other chess players is that he "has
been willing to give up his personal life" for chess.
Roberts, Richard, Harold C. Schonberg, Al Horowitz, and Samuel Reshevsky. Fisher/Spassky. 1972. New York, New York: The New York Times Book Company.
Also don't forget a mentor. When practicing the Martial Arts one always needs a master to guide them, to feel the ebb and flow and to keep a clear mind and focus. You need harness the power of patience, and tame your fear and use it! You need to be at one with the universe, every breath you take is to achieve inner peace and help regulate your energy. Such will help you calculate as far as you need to get ahead.
Anyone can calculate 10 ply (5 moves) ahead easily and clearly, but can you do it with many noisy distractions? Botvinnk, that most wise and humble grandmaster whose teaching methods even today are implemented, had his students practice in loud and noisy environments to really practice their ability to focus and find inner peace. His spiritual strength was also off the charts, and this greatly contributed to his abilities. Perhaps he even felt that G-d himself provided him with plans and even moves? One can only speculate here.
True he would accuse some students of being weak, but one must never mistake honesty and constructive criticism for personal attacks, as mistaking such would halt one's progress. When said student improves he will look back on his old self and acknowledge that he really was weak after all.