Often the most well thought-out plans fail, the most inner-vetted decisions turn out badly. But they do extremely well compared to ventures undertaken with doubt and uncertainty. Better to forgo projects when doubts stay high, when the path forward unclear, when judgment wavers. If you have deep doubts about success, rivals and others who watch you will quickly turn the fear of failure into a conclusion. Therefore never start a new venture when reason and intuition don't confirm the choice.