I think that my biggest attribute to any success that I have had is hard work. There really is no substitute for working hard.

In this quote, the speaker is emphasizing the importance of hard work in achieving success. They believe that their hard work has been their greatest factor in achieving any success they have had. The speaker also believes that hard work is the only path to success and that there is no way around it – no shortcuts or quick fixes that can replace the need for hard work.