All actions have three key parts to them. The motivation, the act, and then the consequence (the order in which these things need to manifest). Nothing happens without reason first, and nothing can happened without something being affected.
For the protagonist, these things are often (but not always) revealed in this order. The antagonist however, is the component of a story that moves it. This is something to keep in mind. In any narrative, the cause of the conflict is what moves the story. The villain always moves the hero. This is often why the villains are so much more varied than our hero, because the hero only acts in response.
Usually, the antagonist has these components revealed in a flipped order. The act comes first, then the consequence, and finally the motivation. The motivation last manifests in a tremendous number of ways. Often this is the 'bond villain speech', or the 'I have already won' speech. Or sometimes it is the tragic reveal, the villain only was doing this to save his people, or his love, or his children.
This is the basic premise that almost every narration ever written has followed. The conflict is started by the villain's act, then the hero is given motivation, then the climax happens as the hero acts against, then it is resolved, as the consequences are introduced (world is saved/world is destroyed, etc), and then the resolution as the villains motivations are revealed.
