Something that few stories do in any medium is provide the motives of the antagonists and protagonists in a sensible and not clichéd way.
...
In addition to this, almost all characters in different forms of media are completely static in their personality. I can think of few examples of media in which a character fundamentally changes between the beginning and end in any meaningful way.
I respectfully question what media you have been consuming.
I would say that yes, there are basically four plots total and everything else is a remake of one or more of those plots. Every year there are also plenty of movies and books that are total crap. Let's be honest, plenty of people are making money for producing bullshit.
At the same time, any successful story is designed around a plot structure wherein the protagonist grows as a person. The antagonist does not necessarily change as it theoretically matter. Many antagonists (and sometimes protagonists) are written as very paper-thin, black-and-white because it is easier for the writer.
However, motives of any character are not rely to the character alone. The story itself, the situation, determines the motives of the character. Take any bad story and I guarantee you the characters also suck. Even Batman did not escape the crap of
Batman Forever.
I agree, it seems like you've been paying attention to the wrong storys. Also, remember that like 80% of any media is crap, so the vast amount, unless you go looking, is going to have pretty thin plot with characters that don't change. But, something that good authors do do is have dynamic characters, or even a static character that the readers perception of changes.
And letting the player decide how a scene plays out in a game requires tons of man power, although I believe Heavy Rain did it okay.
Community
