Typo

I was at a book store yesterday and picked up a book to read the jacket.  Nothing unusual there, right?  But there was a typo in the description.  A very obvious typo.  I immediately put the book back on the shelf.  I do not want to read a book that has a typo before you even open it.  Why would they do that?  How could they miss it?  I don't know enough about book publishing to say it was the writer's mistake or someone else's.  But no matter who it was, it was a stupid mistake.