Its important to read the bounty rules before participating in that bounty. They might have some rules that will prevent you from joining or probably not following them will lead to loss of funds at the end of the period.
Actually, reading the rules and following it is just a simple task to do, if we don't like the rules then we have to leave and not to participate in the campaign. In some case that rules can be subjective and can be changed in accordance with the project owners and such time, we have the right to complain against them if we don't like it. It also important that BM would have to take care of their participants and not just leaving in vain when there are problems arise.