As per my own observation, the type of business, location, those target audience, while they can be important to consider in building a business, but the most crucial thing to consider first is that if you have a sufficient amount of capital that you will use to make your business comes into possibility.
Money is the most essential thing, that’s why those who don’t have enough amount of funds have been delaying their business, while those who have prepared good amount can easily start setting up their business.
There are indeed many factors to consider when starting a business, with location and audience, as you mentioned, being key. But with online businesses now becoming a reality, sometimes we don't need a strategic location to serve as a kitchen or factory for our own business. I have an aunt who's been successful selling online. She even received some household items for free because companies were interested in collaborating with her, so they gave them away, and the rewards had to be advertised as attractively as possible.
Funding is crucial, because starting an online business requires capital, but it's likely not as large as starting a brick-and-mortar business like a brick-and-mortar store.