There is one special character who represents the argument for an alternative point of view to that of the Main Character. This character, who spends the entire story making the case for change, is called the Obstacle Character for he acts as an obstacle to the direction the Main Character would go if left to his own devices.
As with each of us, the last thing we tend to question when examining a problem is ourselves. We look for all kinds of solutions both external and internal before we finally (if ever) get around to wondering if maybe we have to change the very nature of who we are and learn to see things differently. We can learn to like what we currently hate, but it takes a lot of convincing for us to make that leap.
When a Main Character makes the traditional leap of faith just before the climax, he has explored all possible means of resolving a problem short of changing who he is. The Obstacle Character has spent the entire story trying to sell the Main Character on the idea that change is good, and in fact, pointing out exactly how the Main Character ought to change. The clock is ticking, options are running out. If the Main Character doesn’t choose on way or the other, then failure is certain. But which way to go? There’s no clear cut answer from the Main Character’s perspective.