Francis Crick (1916-2004) was not picked-out as a genius in early life; although his co-discovery of the structure of DNA, his intellectual domination of molecular biology in its golden age, and his role in understanding the genetic code make him a candidate for the single most influential scientist of the late 20th century.
Crick was clearly well above-average in ability, quick witted and had a flair for problem solving; but he was (and remained) an intensely-annoying person with an arrogant manner, a loud voice, and an irritating laugh.
His exceptionally abrasive personality was certainly a factor in holding him back as a young man - but later it became a crucial asset in his major scientific work.
Crick had an intellectually privileged childhood and went to a premier academic school, but failed to gain entrance to his first choice universities, and graduated with a second class degree; and then started but failed to complete two PhDs, despite changing from physics to biology
So that by the time he met James Watson in 1951 he was in his mid-thirties, on the third attempt at completing a PhD and with poor career prospects (having been told by the Director that he was not wanted at the laboratory after the PhD was completed).
He was a failure, who had squandered multiple chances; and people did not like having him around.
In other words, Crick was a very late-maturing genius - both by absolute and career standards, and for his early life (and what are usually the peak years of achievement) he was just drifting and he was going nowhere in particular.
Then he met Jim Watson, was persuaded that the gene was made of DNA, and that the structure of DNA was solveable - and he was off and unstoppable!
This illustrates how vital it is for a genius to find his problem.
Francis Crick was not visibly a genius until he found DNA - yet of course he was the same man, with the same abilities (the same intelligence, the same personality): but until he met Watson and discovered DNA he was unmotivated - or rather his motivation was too fickle, and too compromised.
It is presumably of some relevance that Crick was psychologically very 'normal' by genius standards; in that he was very sociable and gregarious, had a high sex drive; and, in general, wanted the kind of things that normal men want - alongside being very highly motivated to work at his scientific problems.
The relevance is probably that Crick was for many years too easily distracted from his intellectual destiny by 'worldly' matters, and was less aware of his inner compulsions than are most geniuses.
Perhaps this is a pattern for late-developing genius?
This matter of finding your problem is vital; and not only for genius level scientists but for us below that level who are yet very driven and motivated by intellectual matters: to be working in the right area, to have found one's destiny, is something that makes all the difference.
My own experience has some parallels with Crick - in the sense that I did not 'find my problem' until my mid-thirties when I seized upon evolutionary psychology/ evolutionary theory; up until then I drifted from subject to subject through early adult life.
By 35 years old I had been employed at medical school, medical 'internship', psychiatry training, neuroendocrinology research, English literature scholarship, and lectureships in physiology, anatomy, epidemiology and public health...
In my case, this sudden clarity about what I should be doing damaged rather than enhanced my career (as so often happens in modern science), but there was and is no doubt that 'here was my destiny', at last.
So I was far more successful than Crick up to age 35, having done well at everything except the internship - but, obviously, the reverse afterwards; and I am not in line for a Nobel!
But - like Crick - I know what it is to have found your problem, and what it is not to have found your problem.
In later life, aged about 60, Crick left molecular biology and went into neuroscience to work on consciousness which continued until his death; but for whatever reason made no decisive contributions and was just a 'mainstream' member of the field.
Crick's intellectual deficiencies, in particular his rather crude 'shallowness' as a person and his strident atheism, indeed made him especially un-suited to working in the field of consciousness; where he never really even grasped the scope and nature problem (leave aside solving it).
Also, by the time Crick went into neuroscience, science was becoming very corrupt - and neuroscience was one of the most corrupt parts (because it was so lavishly funded) - so most of the papers Crick will have read (and he read far too much!) were dishonest and/or incompetent - so the data he was working with was unsuitable for theoretical purposes.
Altogether, the life and work of Francis Crick makes a very interesting and relevant study - as perhaps the last British genius to be famous outside of science professionals.
Note: There is a stylish, concise and scientifically-informed biography: Francis Crick by Matt Ridley - 2006. Also, here is what I wrote after Crick's death: