What it means is to do more than is asked or expected of you. Many question that philosophy: "Why would I do more than I need to? Why would I put in effort that isn't necessary? What would be the advantage of doing more than is required to get the job done right? And those questions are legitimate. The very words used give the answer: "need to," "necessary," and "required." The answer to all is YOU DON'T. That is the point. Everyone does what they "need to" or what is "necessary" or "required." Doing more sets you apart - makes you different - draws attention to what you do and how you do it.
Always do more than expected or that you have to to get the job done. That doesn't mean working harder, it means working with excellence and with the attitude that any job worth doing is worth doing better than the other guy.