How To Evaluate Your Invention's Potential

How can I evaluate my invention's potential?

I have a unique way of evaluating whether an invention will work in the consumer marketplace, because when you're making an invention, you're making it to sell, and you need people to buy it. So you have to be real with yourself and say, will this sell in the marketplace? The first thing I do is I look at the idea and I do research to determine how many people would use this idea. Let's say I have an invention for a tennis racket to reduce the amount of friction when the ball hits the racket. I would then research how many tennis rackets are sold. That's your baseline. Then I calculate out, how many retail stores are there? And then I calculate out, how much can I sell this for? Then I do some research, and if I find that there's enough volume by looking at my market space, then I'll pursue it.