Why is it that the majority of highly talented kids never go on to become eminent adults in their field of giftedness?

Came across an interesting article on the Northwestern University website that discusses some of the personality characteristics of those who do actually go on to become eminent adults; here is a summary:

• Preference for solitude which typically begins in childhood
• Lack of concern with conventionality, especially social conventions
• Extraordinary ability to cope with tension. History of stressful
  childhoods with tense and even traumatizing family situations
• High drive and energy. Workaholics. Many forego marriage, children and other normal joys of life because they fear it will detract from their dedication to their work

Another interesting factor mentioned in the article, which I’ve heard before, is that many eminent individuals lost a parent in childhood or adolescence.