A book is something that you can point to and say "I made that". Regardless of the content, a book is not fleeting or ephemeral. These days people will even loo

A book is something that you can point to and say "I made that". Regardless of the content, a book is not fleeting or ephemeral. These days people will even look up to you if you are capable of reading one. So it carries weight, both in the physical and mental sense of the word. If you're not self published, a book is also a sign of approval. Someone who knows about these things thought it was good enough to print. Really, there are lots of reasons to want to write a book.