I must admit it is the book cover which draws me to a book (whether it is online or via a bookshop unless I know of the author. Know I like their work, can’t wait to snap up the next they bring out etc).
But after that it is the book blurb which draws me into buying the book or leaving it on the shelf. I like something crisp and snappy to lure me in but they’re not the easiest things to write. You can be sure what you see on the book is the result of several drafts!
But the end result is usually well worth it. Every writer needs to be able to sum up their book in a line (as it gives you something to tell people without going on for too long - and that is an art still).
Sometimes I’ve come across quizzes and the like where you have to guess the book from the blurb that’s been given to you and that can be fun.
As a flash fiction writer having to stick to a tight word count, I guess I may have an advantage here. Writing tight can help you produce those blurbs or at least be less nervous of coming up with something short and snappy.