Fine short story writers are unlikely to become great novelists  Short story writers must master the ability to interweave the many small details that together allow mundane incidents to illuminate important truths  Because the novel drowns in such detail, novelists must focus on larger matters
Only a few writers possess both the ability to weave together many small details and the ability to focus on larger matters
Those who excel at one sport are unlikely to excel at another, because it is rare for someone who has the specialized talents necessary for success in one sport to also have the different specialized talents necessary for success in a different sport.