Online social networks used to attract many users. However, in recent years, some users have become less active. Paradoxically, online social networks, which are supposed to help forge friendship, may actually jeopardize the relationship. Through a qualitative study, we offer a new perspective to explain why some people decrease their use of online social networks. Our preliminary findings show that in some conditions, online social networks do not improve but instead jeopardize friendship. Initially, active interactions prevail in online social networks because people are motivated to keep in touch with friends and enhance friendship. However, these active interactions may backfire, and turn destructive. Two pairs of contradictions within a relationship, which are similarity-difference and reciprocity-independence, would help explain such negative consequence of interactions. Users evaluate friendship using criteria of “similarity” and “reciprocity”, but these two criteria vary over time and across friends.