In the device’s latest update, Amazon has given Kindle users the ability to organize books into collections. One way of adding a book to a collection is to open the book’s menu, select «Add to Collection…», and pick a collection:

It’s the default choice, so pretty quickly, you start selecting it automatically. Until you try to add a sample chapter to a collection:

Suddenly, the default choice is «Buy This Book Now». I suspect I’m not the only one who bought a book by accident while organizing books into collections.

This is exactly the kind of thoughtless interaction design that makes people afraid of using electronic devices. I’m quite sure nobody ever accidentally bought a book while organizing physical books on a bookshelf.