I totally disagree.
Yes, you need to head-check the ideas you are passionate about and see if they can really grow into viable businesses. But you also need to check seemingly lucrative ideas and see if you are passionate enough about the industry and the concept to stick it out for the long term. You are entering a marriage. Can this idea be both a great, supportive partner and your best friend?
After the initial buzz of building a business and the early success, what's left over is a lot of time focused on your product and industry. If you don't like golf, you probably shouldn't start a golf-focused e-commerce site.