This feature will only affect News Feeds; all posts will still be displayed on your Timeline. Post targeting helps you share the most relevant content with your audiences, which could help to decrease the number of fans who unsubscribe or unlike your Page.
Additionally, as Inside Facebook noted, this could also lead to a spike in engagement This metric by allowing you to create multiple posts per day without overwhelming your fans.
Jennifer Beese: Jennifer Beese has worked as a community manager and social media strategist. When she’s not writing, you can find her studying anatomy and physiology—she literally has a skeleton in her closet—or under the stars with her telescope.