Most people do not get paid to do their hobbies. (Trying to make money off your hobby could actually ruin it.) 

No matter your passion, it will ebb and flow. Actively cultivating passion, to love your job—whatever it happens to be, is a more resilient strategy than passively expecting passion to carry you through your work.

The best business you can build—and the best job you can have—is the one where you build and maintain a business model. It’s a foundation that creates value for others, gets you and your team paid, and enables you to commit to it over time.

Thanks to Seth Godin (“Passion and our Business Model,” in This Is Strategy) and David C. Baker.