I'm of the belief that Matt Reeves' War for the Planet of the Apes is one of the best films of the year. It's the kind of film you have to really nitpick to find flaws in, but one tiny thing that comes to mind was, in fact, covered in a deleted scene.
The scene, which isn't embeddable, is over on Collider. It shows Andy Serkis's Caesar, pre-Weta magic, talking to the Colonel, played by Woody Harrelson. The Colonel explains that he had previously encountered a human that had very nice things to say about Caesar. Caesar knows it can only be one person, Malcolm, the character Jason Clarke played in the previous film, Dawn of the Planet of the Apes. If you want to watch the scene, go do that, cause I'm going to spoil it in the next paragraph.
The Colonel tells Caesar that Malcolm pleaded with him to make peace with Caesar, because Caesar was a good leader. That never happened, though, so Caesar asked what happened. "I shot him," the Colonel says.
That explains that.
Since a good amount of time had passed between these two movies there didn't need to be a mention of Malcolm, who tried to make peace with Caesar at the end of the last film and went off with his people. His role in the whole thing had already concluded. But, since these stories are connected, it's nice to know the dots did connect, even if it didn't make the film.
Most likely, the reason the didn't it into make the film is — besides tying up that minor loose end — all it does is make the Colonel more evil. And he's already really evil, so it's kind of a redundant moment packaged with a needless, albeit interesting, piece of information. Also, Matt Reeves could just put it on the Blu-ray instead, which is exactly what he did.
War for the Planet of the Apes is now available both On Demand and on Blu-ray.