I often hear writers lament the dearth of extensive character development in feature films. They complain that movies are too focused on action and not enough on personality. While I agree that those are important things to learn about characters, movies are not the ideal medium to learn this information.

Only A Portion Of Limited Screentime

Personality is something that you gather over time, not within two hours or so. A movie is limited in time and any single character is rarely on-screen all the time or always the focus of the story. No matter how much personality you try to squeeze into a film, you will never have enough to satisfy.

Only Equals 3 TV Episodes

A movie feels long when you're watching it, but they rarely extend beyond 180 minutes. Most films are two hours or less. This puts it at a distinct disadvantage in character development possibilities. Two hours is the length of time that three hour-long network television shows would run (40 minutes each). TV series' are often canceled after that many episodes and I have yet to hear fans cheer that they got enough of the characters by then. One season is the minimum unit and that includes at least 12 episodes and up to 24 (or more). For a TV series to feel somewhat complete it need be at least 8 hours long, so a 2 hour movie doesn't have a chance.

Only 40 Novel Pages

The screenplay of a two-hour movie may last 120 pages, but the equivalent in prose is much less. It generally takes about 2 and a half minutes to read an average page of prose, which would mean only 48 pages could be read by the time the movie run-time elapses. Novels are usually around 300 pages, and in fact many readers who love the characters wish some were much longer. It might take 12 and a half hours to get all the information in real time from a novel as you would in a movie.

Limited Situation, Limited Characters To Interact With

Not only is a movie limited in duration, it's limited in circumstance. With the emphasis necessarily on one or a few characters, the number of people any character interacts with will be limited. It will be necessarily simplified due to length and the general cinema aesthetic. Along with a smaller number of interactions with other characters, there are corresponding restrictions in regards to situation. There won't likely be as many scenes of dialogue and nearly zero situations of inner conflict. Dialogue isn't the thing the big screen does best and only voice-over or on-screen titles can portray inner thoughts.

Movies Thrive On Extrapersonal Conflict And Visuals

The cinema has things that it does well and ill. The screen is bigger, the audience is not quiet, and the time you spend in there is comparatively small. So there will be an emphasis on that which it does well. It will tend towards visuals. This could be as simple as walking or as descriptive as a wide shot of a valley where a story is set. These things take time to watch and necessarily will cut down on any character developments.

Big, Goal-Oriented, Not Mundane Everyday Life

Movies don't do slice of life that well. Many writers and aesthetes lament the lack of these stories in cinema, but the medium works against this type of narrative. Movies are short, on big screens, with loud audiences. People don't eat popcorn in stage play theaters, because the dialogue is important. TV shows work well on small screens because the visuals aren't the most important thing. Slice of life is casual and every day stuff, we don't go out of the house for normal stuff. The movie-going ritual demands a story that requires the utmost of its characters. This often translates to highly goal-oriented characters put in extraordinary situations that they will never be in again.

Only One Major Aspect Of Character

Not only are films limited in time, situation, and interaction, they are limited in what you can actually concretely learn about a character. If something they do is a pattern, it can become part of their personality. Movies don't last long enough to establish credible patterns for characters. Over time you can get a sense of a person by how she talks to others, but movies are limited here. The one thing you can learn of a character that is definite in a film is deep character. Not characterization, but the deep, fundamental nature of a character: how they react under pressure.

Movies are a limited medium, there is no way it can effectively compete with others with superior qualities. Instead of railing against the medium's aesthetics, use what it does best to the utmost. Instead of filling the movies with everything, parse it out over a number of media.