Facebook's chief executive, Mark Zuckerberg, said the aim of the algorithm change was to strengthen bonds between users and improve their well-being. Facebook would encourage people to interact more with friends and family and spend less time passively consuming professionally produced content, which research suggested was harmful to their mental health. Within the company, though, staffers warned the change was having the opposite effect, the documents show. It was making Facebook's platform an angrier place. Company researchers discovered that publishers and political parties were reorienting their posts toward outrage and sensationalism. That tactic produced high levels of comments and reactions that translated into success on Facebook.