Anyway, I'm reading The Aeneid there, and once again I marvel at how even the earliest (great) authors understood the need for motivation, but also the importance of hesitation. Here's the very end, where Aeneas has his enemy on the ground before him, begging for mercy:
Lifting up beseechingly his humbled eyes and suppliant hand: 'I have deserved it,' Turnus says, 'nor do I ask for mercy; use thy fortune. If an unhappy parent's distress may at all touch thee, this I pray; even such a father was Anchises to thee; pity Daunus' old age, and restore to my kindred which thou wilt, me or my body bereft of day. Thou art conqueror, and Ausonia hath seen me stretch conquered hands. Lavinia is thine in marriage; press not thy hatred farther.'
Aeneas stood wrathful in arms, with rolling eyes, and lowered his hand; and now and now yet more the speech began to bend him to waver: when high on Turnus's shoulder appeared the sword-belt with the shining bosses that Aeneas knew, the luckless belt of the boy Pallas, whom Turnus had struck down with mastering wound, and now he wore on his shoulders the fatal ornament. As his eyes drank in the plundered record of his fierce grief, Aeneas kindles to fury, and cries terrible in anger: 'Mayest thou, thou clad in the spoils of my dearest, escape mine hands? Pallas it is, Pallas who now strikes the sacrifice, and exacts vengeance in thy guilty blood.' So saying, he fiercely plunges the steel full in his breast. But his limbs grow slack and chill, and the life with a moan flies indignantly into the dark.Now what has happened is Turnus has challenged Aeneas to single combat, and lost. And Aeneas is about to kill him, but hesitates when T begs for mercy and mentions his soon-to-be-bereaved father. This plea almost works-- Aeneas also had a beloved father (Anchises-- notice that Turnus mentions him).
The hesitation is what tells us what matters to Aeneas enough to still his vengeful hand-- the mention of his father. Without that hesitation, we would not have gotten that glimpse of what he values more even than victory.
The hesitation is important, as it shows him in conflict-- his empathy gets in the way of his goal. When there's conflict, it should come out in the narrative somehow, maybe in his inner thoughts (as here), but also in his actions (he lowers his hand).
I think this is an important lesson we should learn-- it's the hesitation that tells the reader there's conflict. The hesitation indicates there's a choice that must be made, but there wouldn't be a choice at all if there was no conflict (Aeneas would just kill him without considering an alternative, if there was no conflict). It's important to SHOW the hesitation when there's a conflict.
And it's important to give characters choices. It's only through making choices that they grow, and it's only through seeing those choices that the reader knows the character (this character values family more than vengeance; this character cares more about money than his daughter -- "my daughter! my ducats!"). The hesitation tells us that it takes some thought to choose.
But just as there's something that happens externally in the scene that shows motivation for the hesitation (Turnus's plea), there should be something external that motivates the action that shows what really matters.
In Aeneas's case, his gaze falls on the belt that he knows once belonged to Pallas (his protege), killed by Turnus. Turnus is wearing the belt as a trophy of war, which isn't outrageous, given the customs of the times, but still is enough to remind A of why Turnus should be killed-- he is the enemy, and he gave no mercy to young Pallas.
That belt is the external manifestation of his motivation (it's important that it's external-- real, powerful, concrete, not just in his head), and serves to remotivate him. In fact, it actually intensifies his motivation to the point that no plea is going to make him waver. Notice how neatly the remotivation fits with Aeneas's values AND Turnus's plea. It's all about fatherhood! Turnus begs him to consider "my aged father" and mentions Aeneas's own late beloved father. But Aeneas is a father too, a surrogate father to Pallas-- he promised Pallas's own father that "I will treat him as a son." So Turnus's plea is about fatherhood, a father's grief, and Aeneas hesitates because he thinks of his own father. And the remotivation is also about fatherhood-- a father's vengeance. This of course amplifies the cultural subtext (Virgil was writing to Romans, presenting Aeneas as the "father" of Rome).
So both steps here-- the hesitation and the remotivated action-- are linked because they each show (in different ways) what Aeneas really values.
I notice that Aeneas's intended action actually gets fulfilled, that is, before the plea he intended to kill Turnus, and after the remotivation, he does kill him. So in a way, that passage of hesitation and remotivation changes nothing-- Turnus still ends up dead at Aeneas's hand. But see how much more interesting the scene becomes when the new conflict (pity) is introduced. And it also serves to deepen the characterization of Aeneas, as we see that he is more than just a single-minded warrior.
Usually a scene changes or obstructs a character's agenda, because it's that sort of interference that really changes the character and impels the plot forward. (I mean, if Mary starts out the scene planning to get out of work on time so that she can meet her buddies for happy hour, you would usually make things happen that mean she can't get out of work on time.) That's pretty standard scene design, and usually works well by focusing on change.
However, sometimes the scene protagonist's agenda just has to be fulfilled. (This is especially true in the last two scenes of the book, because you are aiming at resolution there!) Who this person is and what he wants -- his agenda-- might, sometimes, have to be fulfilled, just because, well, that's necessary for the story. However, as Virgil shows in fulfilling Aeneas's agenda of killing his enemy, the scene doesn't have to show a straight line between plan and fulfillment. You can put obstacles in the way to make the scene more active and dramatic-- and to make the character work for whatever he wants. AND, if you challenge yourself, you can even come up with obstacles that are external, but also reveal something about the character and also amplify the story's themes. :)