The Bible has been very successful as intended, a guide for humanity.
Has it? How are those who follow the Bible more moral, happier, or in any way better than those who don't? I submit that the Bible is an awful guide for humanity. The OT is a complete nightmare and should be thrown right out unles we think morality is about telling women they can't talk in church, owning and beating slaves, or giving your daughters up for gang rape. The OT is one of the most violent, xenophobic, misogynistic books ever written. Most Christians realize and will readily admit this.
At best you can pull some good stories out of the NT, but even that is based on interpretation and there is plenty of craziness in there too, including Jesus' support for the laws of the OT, Jesus explaining how most people will go to hell, how the Jews will be cast out with the wailing and the gnashing of teeth, a perplexing story about Jesus sending demons into pigs, Jesus saying he didn't come for peace but to set family members against each other...most of it has very little to do with modern moral issues.
If you cherry pick and focus in on "love thy neighbor" and "turn the other cheek" you can maybe say some good lessons can be pulled from the NT. But mostly the message is still simply "worship me or burn in hell."
And anecdotally, how do we see people behaving who follow the Bible? There were generations of Americans who owned, beat and raped slaves quoting Bible verse to justify their actions. The attrocities of the Catholic Church in the past...following the Bible as their moral guidline...are well documented including the millions murdered in the crusades and the inquisition, and hundreds of thousands more in the Pope-led witch hunts. "Biblical Morality" didn't stop thousands of priests from molesting children, nor did it stop Pope after Pope from covering up the problem and protecting the molesters. Do Biblical followers divorce less frequently, or cheat on their wive less frequently. No, in fact studies show Christians divorce more frequently than atheists, and there is no different in the statistics on infidelity. And today those that follow the Bible the most closely are out holding "God Hates ****" signs, protesting gay rights, while Christian politicans and other Christian leaders say things like we should put gays and lesbians behind fences, dropping them food every now and then (Charles Worley) or that the government should be killing gay people (Curtis Knapp), and refuse to issue legal mariage licenses (Kim Davis).
How could any of this have happened when these entire societies were being morally governed by the Bible? If the Bible was such a great moral guide, wouldn't we see better behavior from it's adherants? I ask you, where is all this good behavior the Bible causes in it's followers?