What is Fastai? Why do I need it?
Something as basic as an elevator speech that introduces your product in your github page and book intro can mean 10x or 100x more sales.
If you force people into having to search it for you, you have already lost most of them.
For this author it is as you already know everything about Fastai, but if you did, you would not be needing this book in the first place.
It happens a lot to technical writers because they have spent years thinking about a topic, so they could not put themselves in the shoes of someone who does not.