One of my advisors once summed up aviation-as-a-hobby in one sentence: "The times in your life during which you've got adequate free time to devote to the hobby

One of my advisors once summed up aviation-as-a-hobby in one sentence: "The times in your life during which you've got adequate free time to devote to the hobby, you don't have the money... and when you've got the money for it, you don't have the free time."