What’s the big difference between a professional and a hobbyist?
Professionals do what they love even when they don’t feel like it.
Hobbyists do what they love when they feel like it.
In the end, all the other differences – proficiency, expertise, income, longevity, impact – come from this difference.
If you want to make a living at your art, you have to be a professional. And that means doing what you love even when you don’t fee like it.