New South Wales has produced a lot of top-level cricketers. However, not all of them have gone on to represent NSW at a first-class/List A level. Many have switched loyalties, such as Sir Don Bradman (SA), Phil Hughes (SA), Adam Gilchrist (WA), Adam Zampa (SA) and Usman Khawaja (QLD). Others, such as Nathan Lyon, may have started their careers elsewhere (Lyon himself started at SA, although he is at NSW now).
Is this a function of population (NSW is the most populous state in Australia), or is there something deeper? Or am I wrong about this "phenomenon" (that NSW has produced a lot of cricketers of whom many have gone on to play elsewhere) in the first place?