Mary-Kate and Ashley Olsen were ''hard workers as kids.''

The actresses-turned-designers - who have been working since they were nine months old - believe they have a strong work ethic because they were raised to give everything 100 per cent and to learn valuable from their failures.

Speaking to WWD, Mary-Kate said:''We were always hard workers as kids. It's just the way we are, the way we were raised. Our work ethic was everything, and that never left us.

''We like to work hard, and we like to try to do everything 100 percent. In fact, it's actually almost impossible for us not to. Sometimes you succeed and sometimes not so much, but it's learning.''

The 27-year-old twins - who starred in their own TV shows and movies about themselves - admit they had a ''business woman'' head on when they were youngsters and never really saw themselves as actresses.

Ashley explained: ''I always looked at myself, even as a kid, as a businesswoman.''

Mary-Kate added: ''With what we were doing in business when we were younger, I don't think it ever felt like we were actresses -- because we spent so much more of our time not in front of the cameras, building a brand.''