The more I talk about the ideas of pacing, audience attention, and communication in trailers, the more I realize these ideas are universal. This is because by and large, stories and media are made for other humans. To make good trailers, I think it's good to take inspiration from other forms of storytelling.
Trailers are a unique art form, but I don't want people to think there is some sort of magical formula which only applies to trailers. I think when we want to know how to do something well, or make something good, we tend to look at things in isolation, whether it's making a trailer, a game tutorial level, a short film, an instructional YouTube video, a TED talk, a magic act, a stand up comedy routine, a dance, or anything else which is intended to hold an audience's. But because human beings are the audience for all of these things, lessons for one can be applied to the others.
We can get very stuck in a very myopic mentality that everything is its own thing with its own set of rules, when in fact there are lessons we can take from one thing and apply them to another. It's a matter of recognizing the connection or relationship between what we know, and what we don't.
A perfect example of this is my friend Warren, who I met one morning a few years ago while I was practicing kung fu in the park near my apartment. Just to paint a word-picture, Warren is an African-American gentleman in his late 60s; he was curious about my kung fu, and asked me if I taught. I said I didn't, but if he brought some sweat pants and comfortable shoes, I'd show him some stuff. Since then I've been teaching him as much as I can. He's learned a LOT in that time, but there are still moments when I can tell he's making unnatural movements with his body because he thinks they're "correct."
For example, when performing an inside crescent kick, I've told him to first move his body by turning and/or looking to the right or left, and then to let his leg follow the body's movement. He often does the exact opposite of this, which is to move his foot first, and then the body turns last. Because he's thinking of performing a kick, he naturally fixates on the foot and the leg, and forgets about the body.
What he forgets in that moment, are all the times in his every day life when his legs follow his body's movement when he does something as simple as walk. If you're capable of walking, it's so natural, you might not even realize when you walk, your body moves forward first, and the feet play catch up the entire time.
If you can, try it out right now; just stand and walk a few steps.
Did you notice how your body moves first, and then your feet lag behind until you take a step forward? Now try walking forward by keeping your body still and moving your feet forward first.
How did that feel? Probably pretty unnatural.
The point I'm making is, Warren thought to himself: "This is kung fu, the movements I'm learning are unique, and only apply to kung fu." I'm doing my best to tell him: "Kung fu is about moving your body in a specific way, but don't ignore what you already know about moving your body, just add the kung fu ideas on top of it."
So, if you know how to do ANYTHING which relates to holding an audience's attention and entertaining them, use that to inspire you to make better trailers.
There are SO many things which aren't trailers or related to advertising which follow a lot of the same principles and processes.
This is a great video by Matthew Encina about how he structures his YouTube lesson videos.
This is a great video by Game Maker's Toolkit about pacing and engagement in video game design. And while we're at it, this GMTK video about making levels in Mario Maker also has good ideas about pacing.
I could go on forever because all of these art forms are fundamentally about entertaining, holding audience attention, and communicating. Everyone figured out humans quickly get bored, and need a change of pace in order to stay completely engaged. If you're struggling to make a good trailer, try to find lessons you might already know from a different discipline, and apply it to trailer making. Just speed up the pacing and make everything shorter :P