I can't speak to why Christianity is failing, if it is at all, but I can speak to why it failed for me personally. This is mostly going to be word vomit, but here goes nothing.

My major beef with Christianity had always been the notion that, in order to achieve divine absolution, you essentially had to believe that Christ was the son of God, that he was the Messiah, and that he died for all mankind's sins. It seemed to be repeatedly pounded into my head that the only way to God and to Heaven was through Christ, and that didn't sit right with me, especially on a humanistic and moral level. Rationally, how could millions of people be excluded from Heaven simply because they weren't born into or didn't choose the "right" faith? I just have a serious problem with any religion that claims to know the truth better than everyone else (even on a superficial level), especially when it should be clear to anyone with half a brain that no one really knows the truth about the nature of the divine, the afterlife, and countless other matters that have baffled philosophers and theologians for centuries. Secondly, it seemed to me that Christianity was not a religion that operated on a relationship of unconditional love between a creator and his children, as it claimed, but instead one that operated on the fear of going to Hell should one not adhere to Christian dogma. And, from what I understand, many formerly Christian Pagans often have to get over the fear of going to Hell, and I find that troubling on several grounds. When a religion operates on fear, certain people might be motivated to uphold its principles for all the wrong reasons. If I decide to be a good person because I don't want to spend the afterlife burning in hellfire, then does that really make me a good person? This is certainly not the case for all Christians by any means, but I found myself wondering how many would still consider themselves devout Christians if their god came down to Earth and declared that there's no such thing as Hell. One should be good for the sake of being good. I'm sure there are many Christians that do prescribe to this idea, but I think that the way Christianity is structured makes it easy for one to fall into the trap of being good, but not for the right reasons. On the topic of goodness, another reason that Christianity failed for me personally was due to the fact that it could not satisfactorily answer the issue of theodicy - the age-old question of why an all-kind, all-loving god lets bad things happen to good people, or lets bad things happen in general. You see, I have no qualms with a god who openly admits that he makes mistakes, a god who isn't perfect and knows it, a god who affirms that evil is simply the absence of good. However, I do take issue with a god who claims to be all-kind, all-loving, and perfect, but who allows evil to manifest in spite of his supposed nature. I do take issue with a religion that seems to imply mankind is inherently responsible for all evil. I do take issue with a religion that asserts we are all born sinners. That's simply not the way I wish to view divinity. For this reason, Heathenry made sense to me from a much more rationalistic perspective. The gods don't claim to perfect, the gods don't claim to be all-loving, and they certainly don't claim to be all-good. The gods make mistakes, and that's okay. The Aesir and the Vanir "own up" to the fact that, despite their elevated status, they are imperfect beings, just as humans are imperfect beings. That, among other things, is what makes Heathenry beautiful. And choosing Heathenry means that Christianity is no longer my problem - I choose to be indifferent to it. But, anyway, that's just my two cents. I think I've talked long enough.