In my opinion, what makes a work smart is the thought stirring the work and what makes a work hard is the energy and consistency it requires. So in order for one to make it in life, one has to adopt both. Some people work hard consistently without being successful at such work, while some people think smartly, without having the energy and staying power to do the work behind the smart thought. So anyone that wants to be successful will have to combine both hard work and smart thought and the result of such combination is smart work.