I learned about information asymmetry in a class at university. I learned that books are one of the products with a large information asymmetry.

One of the reasons I find it difficult to buy is because we don’t know the contents. Even if it’s a book that you open, it’s hard to read it all in a bookstore, and we can only glance at it. It’s hard to buy something when you don’t know what it’s all about, and there’s a risk of disappointment.

There are many types of books, but I would like to use reference books as an example to think about what the seller and the buyer are each trying to do.

The risk for sellers of reference books is that even if they make a good quality reference book, they will not be able to get people to buy it if they do nothing with it. For this reason, I believe that the cover and obi (belt) of a reference book should appeal to buyers so that they can compare it with other reference books and prices and choose one that is easy to understand, how easy it is to understand, why it is easy to understand, and what kind of teacher wrote it. I also think that putting the name of a famous teacher or the brand of the reference book series on the cover sends a signal that the book is highly valued and trusted, making it easier for people to pick it up.
Reference books basically come over 1,000 yen, and for a student who buys several subjects, the total cost will be quite high. The price is not enough to forgive a failure, and there is a risk of disappointment such as not much improvement in grades even after using the book. The buyer has to make a decision based on word of mouth, reputation, etc.
There may be third parties such as teachers at prep schools or schools recommending the book, or bookstores putting the book in a position where it is easily accessible.