How simple could it be?
Things work because one believes it will work. It all starts with an idea. If one is determined enough to work on it, success is always there for the taking.
Success depends on how much one is willing to work for it. But first thing's first, one must believe it will work.
If it doesn't, don't give up. Sleep on it. Take a break. Then when ready, go back to the drawing board. Keep your options open. For all you know, solutions can be found only after "thinking out of the box".
If you fail the first time, figure out why and don't do it again.
If you fail the second time, figure out why and don't do it again.
Third time, fourth time, same... don't do the things that failed.
Thomas Edison was once doing an experiment and his associate was complaining about not getting results. The associate proposed to discontinue the project because they haven't made results even after 50 trials. Thomas Edison replied that the 50 trials were itself results telling them that all the things they did don't work.
Off to the 51st trial then.