The following contains some spoilers for Captain America: Civil War.
While Vision and Scarlet Witch both joined the Avengers at about the same time, Vision is still the "newer" of the two, as he was only born a few minutes before joining the team. As a synthetic lifeform created from an artificial intelligence, Vision has a great deal to learn about what it means to be human. According to the actor that portrays him, in order for Vision to truly reach his potential the character must begin to understand human emotional concepts like love and loyalty, something he only begins to get a grasp on during Captain America: Civil War.
Paul Bettany was recently speaking with Entertainment Weekly when he explained that Vision’s decision making process in Captain America: Civil War was based entirely around logic, and as such, it didn’t leave room for his personal feelings regarding other members of the team. What’s clear in the film, however, is that Vision is beginning to have feelings about Wanda Maximoff.
He has logic in abundance. And logic does not afford any room for loyalty. New information could come to light, and he might flip to Captain America’s side. But love solidifies things and provides loyalty. So if he’s there to protect mankind – or frankly, the universe – he needs to figure out what’s good about these creatures, and I think that’s the quest that you find him on. And, of course, in the comics, the relationship becomes romantic. We’ll see moving forward what happens for Vision and Wanda.
While Vision’s reaction to the conflict of Captain America: Civil War is entirely logical, the response from Scarlet Witch is entirely emotional. She feels both guilty and angry about the situation. She blames herself for the disaster which leads to the Sokovia Accords. At the same time, she resents the treatment that she receives from Tony Stark, essentially being held prisoner at the Avengers compound. Vision, doesn’t really understand this, which leads to the conflict between the two. By the end of the film, we see that Vision is in a very different place, sitting in silent contemplation. From the look on his face, we can surmise that whatever he’s thinking about is not strictly logical. Something is bothering him. We can guess what, or who, that is.
It will be interesting to see what the future holds for Wanda and Vision. For the two to be able to build any kind of relationship together they will have to spend time together, something that will be difficult based on where the pair find each other at the end of Captain America: Civil War.