From the White Wolf Wiki, the most complete White Wolf reference

Bystander is the term the Imbued call failed hunters. When the messengers imbue someone they expect them to take action against whatever supernatural incident the potential hunter is witnessing. If the hunter fails to act then the messengers take away all of their powers. Bystanders are cursed with knowing about the supernatural but being powerless to do anything about it. However, a few bystanders such as Moderator87 have managed to overcome their inital weakness and help other hunters.