There is a fantastically gross reason #McChicken is trending and, no, it's not because they're delicious. Here are the reasons McDonald's famous fried chicken sandwich is dominating social media in what could be the world's worst viral marketing campaign.

1. Facebook's Algorithm Has Lost Its Mind

Facebook fired the team of human beings who helped decide what news stories were featured in the social media giant's right-hand trending module. Instead, Facebook let the robots take over. The result? The robot chose hoaxes, stories with cuss words, and pornographic videos instead of, you know, news.