The first thing you can observe in a researcher's profile is how many vulnerabilities the researcher has reported in his bug bounty hunting career. This indicated how much the researcher is active on the platform and how many vulnerabilities he has reported to date. A high number of reported vulnerabilities does not usually mean that the researcher has a positive track record and is relative to different factors. That is, if the researcher has 1,000 vulnerabilities submitted over a period of 1 year, the researcher is quite active.