Because your friend changed the channel.
According to police in Seattle, two women in their 60s were watching TV last Thursday morning, but began arguing after one of them changed the channel to a religious program. Such arguments are common; settling them via stabbing is less common. Police spokesperson Renee Witt said that the woman offended by the channel-change grabbed a six-inch kitchen knife and stabbed the channel-changer. The wounded woman was rushed to a local hospital with serious injuries.
Witt said the nature of the TV dispute was not yet clear. "I don't know what they were originally watching," she said, "but it must have been something really good."