An ego which was ultimately their downfall.

Of all the things the prequels did, making the Jedi surprisingly weak and gullible is one of their more interesting sides. I wonder if it was deliberate or a side effect of bad film making? I quite like it, thinking after Return of the Jedi that "Aha! Luke Skywalker is a Jedi now! The galaxy is saved!" and then realizing that actually, Jedi are still very fallible and, in many ways, closed-minded.