If your talent meets the market, then a perfect conclusion is reached.
If you have matched your list of potential businesses doable by you against the market popularity by offline and online methods and you are able to narrow down on one or two niches then that is the perfect climax your product creation can bring.
All you need then is creation of the product and sales process. But it may always be not so.
Rarely ( I write rarely because this is very uncommon still) your potential list may not fetch you enough market. What do you do then?
Do not worry! This is not the end of the world. It only demands bit of more work. In such a case, you can choose any niche that you have found profitable and you think you can work upon that.
After you narrow down on that niche, you would have to conduct an extensive search on that topic, read and gain knowledge. With time you can become quite knowledgeable in that niche. Do not worry about this time spent in learning because it is an investment. Take out few hours for this purpose after your job/work is over, study and make notes. You would be ready in few weeks. And that diary which you made notes in would be a ready to print book.
Another factor that I would like to discuss is the competition. It is a common occurrence to find a profitable niche full of competition. It is ideal to find a niche which is profitable as well as without competition.
You may happen to find such a niche. Great! Go ahead.
But if a niche is competitive, you should not stay away from it because it is good news confirmed. A lot of people competing in a niche means that there is enough money in that niche.
That does not mean you cannot succeed.
Even if there is a lot of competition, there is always place for the next player.
You should not worry about competition. Every person has a unique advantage over others because none of us are same. When you enter a competition, use your outlook as an advantage.
Put a twist!
Change the angle!
Do something different and you are bound to succeed.
Lastly it may happen that you have more than one potential business which has found hungry market. What to do?
It is very good news. But do not start both your businesses at the same time. First concentrate on one, get succeeded in that and then move on to next product.
Conquer one niche first before flirting with another.