Finding a job where you're a good fit isn't easy either. I'm somewhat temperamental; in a job where I'm uninterested, it's easy to be the worst performer. In an interesting job (for me, these are often what others consider difficult), it's easy to perform several times as well as most others and be the top performer by a wide margin. Admittedly, my ADHD may give me a higher spread than most people, but I imagine it affects everyone to some degree.