"...The desire to do so decreases when I realize I could be spending time on some other, more promising product rather than wasting it on a lost cause." This i

"...The desire to do so decreases when I realize I could be spending time on some other, more promising product rather than wasting it on a lost cause." This is just the shiny appeal of a new idea. If you spend as much time on any of these new ideas as you have on your original, the shine would also eventually wear off. Focus on trying to sell your original idea. Even if it fails, you will learn invaluable lessons.