Earning profit through signature bounty campaigns is not that very simple to say that once you had joined, you are assured to get a bounty reward as there are ICO's out there that do not fulfill their promises or otherwise scam ICO's. I had been into several ICO's but I was once a victim of a scam ICO pprobably because I haven't checked thoroughly on that particular ICO project. I believe that it is very important to do your thing to validate and check properly the selected ICO prior to your participation. Joining ICO is still a matter of luck and for others who happened to be victorious in their bounty participation, they had probably made a depth research starting from the whitepaper, team members of the project, roadmap and the bounty manager that handles the project.