Because a book is a big upfront cognitive investment - and if it's written well, it will begin with the assumption that you already want to use Nushell, because

Because a book is a big upfront cognitive investment - and if it's written well, it will begin with the assumption that you already want to use Nushell, because why else would you have the book? If you want to entice users, they need to see something immediately valuable, and it needs to come with essentially no investment on their part.