In January $Tesla Motors(TSLA)$ Report Chief Executive Elon Musk promised that the company's vehicles would be self-driving by the end of the year."I would be shocked if we do not achieve full-self-driving safer than a human this year. I would be shocked," Musksaidduring Tesla's fourth-quarter-earnings call.He emphasized: "Being safer than a human is a low standard, not a high standard. People are often distracted, tired, texting. … It’s remarkable that we don’t have more accidents."In other words, owner sof Tesla vehicles would by year's end have a feature enabling their cars to drive themselves in any conditions.At the risk of damping the enthusiasm of Tesla fans, the chances that their champion Musk's schedule will not be met again are good.T