There are many reasons Facebook users decide to friend or unfriend someone on the social network. That being said, knowing someone in real life is the top reason cited for friending someone (82 percent) and offensive comments are the main reason someone gets unfriended (55 percent), according to a recent Nielsen study based on a representative sample of 1,865 adult (18+) social media users. The survey fielded from March 31, 2011, to April 14, 2011.
The infographic above lists most of the reasons Facebook users friend and unfriend. Following knowing someone in real life, the other reasons for friending someone are: 60 percent for mutual friends, 11 percent for business networks, 8 percent for physical attractiveness, 7 percent for increasing friend count, 7 percent for friending everyone, 7 percent for quality of photo, and 4 percent for their number of friends. Following offensive comments, the reasons for unfriending someone are: don't know well (41 percent), trying to sell me something (39 percent), depressing comments (23 percent), lacking interaction (20 percent), political comments (14 percent), breakup/divorce (11 percent), don't like their friends (8 percent), update profile too often (6 percent), they add too many people (6 percent), they don't update enough (3 percent).
In short, the research shows real world interactions drive online friendships while sales-oriented and depressing comments help drive friend removals. Facebook etiquette also plays a role: some users take into consideration if you are updating too often or too little, while others just decide they have too many friends.
Men are more likely to use social media for building their career, networking, and dating. More males add friends based on business relationships or physical attractiveness. Women meanwhile use social media as a creative outlet, to get coupons and promotions, or to give positive feedback. Females are more likely to friend based on knowing someone in real life or remove them due to offensive comments.
If you're wondering, adding a friend on Facebook is the same as it has always been: click the Add Friend button on someone's profile or beside someone's name. To unfriend someone on the social network, however, the current method (before Facebook changes it again) is to go to their profile, place your cursor on the Friends menu in the top-right, and choose Unfriend.