In this case, the DJ had the crowd crazy pumped - the strobe lights were going, the music was on point and just when it got to the most awesome part in the song, he hit them with a love song. It's the worst. We're mad and we weren't even there.
There has probably never been a better visual to explain the "WTF" feeling, though. Immediately, everyone who had thrown their hands up in the air yanked them down as the energy was completely zapped from the room.
It's actually so terrible, it's kind of good and almost five million people have viewed the video on YouTube since it was posted just three days ago. So, he might have pissed off the 100 or so people in the room, but he made five MILLION people on the internet very happy.