Can Someone Make Me A Book Trailer?

I would love to see a book trailer that isn't horrible, personally.

But maybe I'm just being cynical...

I've seen one or two that I liked. lol. Would stick my nose in further, but 1. It's not my genre and 2. I'm up to my neck in my own video projects

This is a serious question: Is there any reason at all to believe that book trailers are an effective marketing technique?

Do they reach out to people who hadn't heard of the book and convert them into buyers?

Or do they reach out to people who have heard of the book (but chosen not to buy it up to that point) and convert them into buyers?

Or are they largely ignored?

What are the examples of book trailers that are effective from a marketing point of view?

I don't know the answer - I'm not dissin' on book trailers - there might well be some amazing successes I'm not aware of.

Anyone have the answers?

Mac
(For the sake of discussion I'm not talking about the direct marketing style 'This book has the 8 simple secrets to instant wealth' type trailers)

Book trailers to me are largely dumb looking...I have actually almost been turned away by book trailers. I see it as more of a thing that people that are already fans of the series would enjoy.