Through consecutive Hook cycles, successful products reach their ultimate goal of unprompted user engagement, bringing users back repeatedly, without depending on costly advertising or aggressive messaging. While I draw many examples from technology companies given my industry background, hooks are everywhere— in apps, sports, movies, games, and even our jobs. Hooks can be found in virtually any experience that burrows into our minds (and often our wallets). The four steps of the Hook Model provide the framework for the chapters of this book. The Hook Model