In my opinion, thinking about success and failure is already the wrong path. I would say do things you find intrinsically worthwhile instead. For example, right now I'm developing an online course because I think it's fun to do. If no one signs up, then I'll do something else. If I do get students, I'll do something else anyway...in fact, I never even think about the word "failure". It's just something to do that enriches your life and move on from.