Here’s something that I just realized. Have we ever seen anybody complete their unfinished business and get sent to the worse place? I think the way we’ve been looking at this is Heaven/Hell, but that may not be quite what the show is implying. So far all of the people who have been sent to the worse place or River of Lost Souls were sent there by force, and without fulfilling what their unfinished business was. I guess completing one’s unfinished business is essentially a second chance of sorts, and getting to go to the better place is your reward. Here’s something that Jane Espenson tweeted a while back, regarding this:
@Chipped_Mug7 Not everything you've ever done wrong is included in the Underworld's "unfinished biz" file.
— Jane Espenson (@JaneEspenson) March 21, 2016
Going by what she said, not all sins are taken into account, when it comes to one’s unfinished business.