Let's examine each ingredient one by one. Don't for a second dismiss the importance of this ingredient simply because you can't control it, can't evoke it and may not be aware when it is present. Nevertheless, if all the other ingredients are present and lady luck isn't smiling on you, your chance for success is diminished. Assume luck will be with you and be thorough in your preparation. For most people, the harder they work, the luckier they get.
Research is the key here.
Thorough, well thought out, well planned market research can save a lot of time and money. Before developing a product, you must determine if consumers will want a solution to the problem you perceive. The data gathered to answer these questions must come from a statistically significant number of potential consumers for the product, not from a handful of friends and relatives. Treat everyone you meet as an important resource as you try to develop your project. Who knows, even a casual contact on whom you've made a good impression may provide some help when you need it most.