Criterion of Embarrassment, part 1

One of the things that continually substantiates the authenticity of the Bible to me is the fact that the protagonists of the "story", due to their own actions and choices, are repeatedly portrayed in an unflattering manner. This is most evident in the Hebrew Scriptures (Old Testament), but is also strong, though more indirect, in the New Testament as well.

The Israelite people continually blunder through the pages of Scripture. Failure after failure. Even after God brings about events that are meant to demonstrate many things, among which are His unfailing love but also His demand for faithfulness (in heart and behavior). Many of these events are catastrophic for the fledgling tribe and so you would think they would learn their lesson. But in some cases, they immediately (i.e. Num. 16:41 by the next day) revert back to whatever it was that brought the cataclysm down on their heads in the first place.

Even the heroes themselves- Abraham, Moses, Samson, Saul, David, Solomon, Peter, Thomas, Mark, etc. are prone to failure, and often with drastic consequences. The only exception is Jesus- the ONLY one described as without sin (though not without temptation)- a very important detail to the point of the narrative as a whole.

Now, I would love to compare these portrayals to "other" myths, epics, and legends of history. As the axiom goes, "history is written by the winners." Now, if these are simply stories, and not accurate historical accounts, who in the world would write such a negative portrayal of their own people? Not only that, but throughout history, this particular group has been the target of repeated, systematic efforts for their complete annihilation, why would the authors so frequently highlight their foibles, weaknesses, drastic failures, tyrannies, and treacheries? Wouldn't they rather want to write of their heroics untainted by common human weakness? Or write of their leaders as idyllic figures of which one could aspire to emulate? Additionally, unless the accounts are true and we are not to conclude that the various books of the holy scriptures were compiled by a group of religious power brokers intent on maintaining their sway over the masses, how could you get roughly 30+ authors, some of them officially commissioned by the kings of Israel (some of whom were kings themselves), to agree on such an uncomplimentary review of their history?

Or should we draw another conclusion? Tell me.