Yeah, that's probably my best guess. Although that could just be a game mechanic to differentiate your character from all others. Or living from dead. Or undead. Or something.
The basic beliefs of limbo get more than a tad sketchy (many place it as being a sort of neutral ground for the souls who never took too far to either side, others place it as the afterlife's waiting room since heaven won't exist until after the end of time). But as for general belief, that'd be the "challenge" part of the idea of a limbo. Some move onward. Some give in and become evil spirits. Others stagnate forever. The road to heaven isn't an easy one to take. Some souls simply give up at the sheer difficulty of "cleansing themselves" via a trek through limbo. (like those people who drowned themselves). It could conceivably be an explanation for the later areas being devoid of life. A soul that actually manages to make it to the end of purgatory/limbo is quite rare. Which is why some religions *cough*Catholicism*cough* put in an express lane. But it'll cost ya.