You can't just rely on one idea to get you the gold ring. The market is so fickle, you can have the best selling product in the world this week and be forgotten two weeks later as the new "best " idea hits the shelves. Look at the Cabbage Patch dolls. They are still selling today, no where near what they were at the height of the craze. People were standing in line for hours to get one, fighting each other, and paying stupid prices for them online. If you based your life style on the money you were making at their height you would be in debt over your head right now or foreclosure.
I have had thousands of ideas, but know that all of them are not gems. I have taken the time to do sell sheets for 247 of them. I am currently shopping them around and finding success and failure as I go. I diversify my ideas working in multiple areas such as toys, tools, kitchen, eyewear, and outdoor. I keep all doors open so that I don't miss an opportunity. If one market drops I have the option of working in another that is going up. This way I try to maintain a level of success.