Those involved in the Manhattan Project who were young were doing scientific/technical work. When dealing with organizing and managing a great number of people

Those involved in the Manhattan Project who were young were doing scientific/technical work. When dealing with organizing and managing a great number of people or resources, I have never seen a young inexperienced human performing adequately, even remotely. Old age and presumed experience is not at all a guarantee that someone would be good in such roles, but from what I have seen, young age and the associated lack of relevant experience pretty much guarantees failure in such cases.