Speaking in an interview with i-D about their fashion line, The Row, Mary-Kate said that maintaining a private personal life is part of how she and Ashley grew up.
"We were raised to be discreet people," Mary-Kate said, when asked about The Row's discreet, modest style.
"I think that potentially that's just our aesthetic, our design preference," Ashley added, "But that doesn't mean that we don't also appreciate something truly ornate or maximal. Sometimes a collection even starts quite like that, and then gets pared down. It doesn't always start from that simplistic place."
Elsewhere in the interview, Ashley said that she and Mary-Kate initially wanted to keep their names away from the brand.
"We didn't want to be in front of it, we didn't necessarily even want to let people know it was us," she said. "It was really about the product, to the point where we were like: Who could we get to front this so that we don't have to?"
ANGELA WEISS/AFP/Getty Images
Mary-Kate and Ashley have long stepped away from acting, and are celebrating 15 years of their fashion house. The duo opted not to participate in the Netflix reboot of Full House, on which they starred as Michelle Tanner - though they've maintained relationships with some of their costars.
"Ashley and Mary-Kate. I love so much. When I'm in New York or when they're here, when we can, we see each other," he said on a podcast, according to E! News.
In their conversation about The Row with i-D, Mary-Kate said that she and Ashley are "very much perfectionists."
Kevin Mazur/WireImage Mary-Kate and Ashley Olsen
"We're hard workers and we've always been hard workers," Mary-Kate said, adding that she's "happy" people look at their brand "as a perfect product or products that feel complete, or whole."
"I think the reason we do fashion is to constantly try to fix our imperfections," she continued. "And you have next season to do that. But it's also our job to find every imperfection in there to make sure that we're constantly pushing ourselves and training our eyes and making sure everyone is served. Just evolving and learning."
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Ashley added, "I think it's been really important for us to stay in control and to do things at a time that feels right. That has been the driving force of the brand and there are certain things probably that are accelerated, but there are other things that have slowed down."
"So, I think it's about always finding that balance of making sure you're obviously not behind or slow, but that you're keeping up with the pace of the business in the right way," she said. "Not getting ahead of yourself, but not staying too far behind. And I think that's an interesting balance."