Pick an Interest. You must first choose a niche for your business. This could be anything from cars and electronics, to computers, clothing and food. It is best to select something that interests you and there are many highly profitable niches to choose from. But if you have no ideas on what you like and how to choose a niche Wealthy Affiliate will give you great ideas to pick any profitable niche which still has room to get in to.
In the long-term, it affects your versatility, functionality, and, of course, your brand. In the short term, it can certainly add/take away a lot of headaches. That said, just like choosing a physical house or office, there is no such thing as an absolute “best” or “top” choice. There’s only the right choice relative to your goals, experience, and circumstances.