My main use case for HackerOne is mostly for submitting bugs. I get into the programs listed there, find one that is suitable for me, do my penetration testing on the systems, try to bypass some controls, and if I find a bug, I submit it on HackerOne.
A specific example of a bug I found and submitted through HackerOne that stood out to me involves race conditions because they resonate with me as a unique type of bug. If you can submit simultaneous requests to a program or a system and it fails to queue those requests properly, you end up getting the same response for multiple requests, which I find incredible, so I tend to focus on race conditions.
I use HackerOne as an individual, primarily as a side hustle. While I'm working for the organization, I do projects related to it, but in my free time, I get into HackerOne and try to hack other systems that are not related to my organization, helping other organizations enhance their security.