Doctors are puzzled by the situation and think it has a link to the subconscious. Studies have shown if a person believes strong enough they will die on a certain date the body will actually shut down, killing the said person. Doctors believe the subconscious brain is so disappointed in the general state of the person using this term, that if said enough the brain will cause the body to go into "self destruct" mode.
Doctors have concluded saying YOLO once or twice is harmless but if said hundreds or thousands of times can make the body go into complete shut down mode. Doctors have begun starting a campaign to get all politicians to start saying YOLO at each campaign event in bitter revenge to Obamacare slashing their wages.