Do what you love and the money will follow.
Excuse me while I wretch. I love sleeping and drinking beer. I don’t think following either of those loves will result in any success. Unless…
You should be passionate about your business idea. Don’t let the passion blind you to the obvious necessities of finding customers, managing employees, marketing, etc. But you’ll need that passion to help you deal with all of the stresses of the business. If you’re not passionate about selling cars, don’t open a car dealership. The mundane will kill you if you an’t fall back on your passion. But if you love cars and working on cars, should you open an auto mechanic shop?
Probably not. Use the discipline of creating a business plan to determine if following your passion, in this particular way, will actually work. You may not be able to share your passion with other people willing to give you money (customers). Without customers, there is no business.
On the optimistic side, once you’ve identified your passion and started a business plan, maybe you will an alternative business. Maybe you don’t need a full mechanic shop with all of the overhead and employees. How many oil changes at $29.95 do you need to do just to pay rent? Are there enough hours in the day for that. Maybe you find a niche that lets you follow you passion, like auto detailing, dent repair, a car shopping comparison website and so on.
Don’t necessarily let your passions drive your decision. Let them be a spark but follow your discipline.