I find that having a high cost of travel in BW is challenging. Once you leave an area, a lot of beliefs get sidelined. Not only this, but wises, circles and relationships often become less useful as well.
Not having a strong, urgent situation also contributes to belief churn IMO. Players are using their beliefs to try to engage with the setting, but without group commitment that signals this story avenue is here to stay, the beliefs are tentative and readily abandoned as soon as something more interesting comes along. This makes it hard to put beliefs in conflict, since players aren’t invested.
The other belief-fizzling scenario I’ve had more than a few times is the immediately-irrelevant belief. A player realizes a belief is irrelevant, and he quickly fills it with something that looks good given the current (but rapidly changing) situation. So often these short-circuit - they get completed five minutes later, and it seems lame to award Persona for them before the player has done much at all with it, so they’re quietly erased.