WHY IS THE FILM TRAILER MADE?

Using Film Space's site, I next investigated how the film trailer helps audiences understand the genre of the film through the action presented. The first task was to look at the images of three trailers before watching then guess what the films might be about: I guessed that Churchill would be a historical biopic, Spiderman a superhero fiction film and The Red Turtle a documentary about adventures underwater with turtles. I then watched the three trailers, The Red Turtle, Churchill and Spiderman.
1. I guessed wrong about The Red Turtle which turned out to be a Studio Ghibli animation fantasy about a castaway who braves life on a desert island where red turtles befriend him. I think that the image below is of such high quality that it looks filmic, rather than animation, so seeing the whole trailer would help me decide whether I wanted to see an animation or not. Animations often have children as their primary audience, although personally I love Studio Ghibli work, such as Spirited Away.
2. As expected, Churchill is a biopic that lionizes the Prime Minister and depicts him as a strong protector who needed to stand up for his country and lead the Allies during a time of national peril.
3.Spiderman is a predictable superhero action adventure blockbuster that prioritises spectacle and action but entertains through comedy as well in a 'save the world' scenario. The young Spiderman is tested and meets the challenges he faces. As part of the Marvel franchise, it promises its target audience high production values and an action-packed narrative.
The trailers helped me  understand the genre of the film.
Did any of the trailers seem to fit more than one genre? Spiderman is a superhero action adventure comedy hybrid, that is also a 'rites of passage' film about a young man finding his feet. Churchill is a historical drama as well.