Well this question is exciting because why it seek knowledge and experience, and when it comes to this one need to seek and research for your self. It hard to be able to predict the future of any project because of his volatile the market can be but again once you go through the white paper and teams and the product onces those things suits you and roadmap OK then you just take the risk to participate in they bounty.
Not that exciting though. You are right about determining a project's future is unpredictable. It's not easy to know if they'll be having a good future if at the beginning they look good.
But at the end and during its process on listing through exchanges, they will be dumped by everyone who got the reward from that bounty which were mostly blamed not only by their co-bounty hunters but also by the investors.