If fashion trends are meant to be a sign of the times—from Millennial pink to athleisure at the workplace—then the state of the trend itself can also be an indicator of the ebb and flow of culture. And as the fashion industry matures in the digital age, trends are not only coming and going at different rates, (is merch really dead?), but also emerging from new and varied sources. Every day it seems there's a new trend to know about, so much that it can be hard to keep up.

So today, as we begin to enter not only a new season but also a new age (Mercury's finally out of retrograde...), it's useful to ask: Where do trends come from? Are they cycling faster than ever before, or not fast enough? And what eventually kills them? And who better to answer these questions than buyers, who spend their days gauging not only what's trending, but also thinking about what real people want, and why.

“For so long, trends came from pop culture and the runways," said Roopal Patel, the fashion director at Saks Fifth Avenue. "But these days with technology, trends are also coming from much more obscure resources and places than one would think."

In addition to trends now being dictated by teenagers on Instagram—they're also coming from different areas of culture, Patel elaborated. As we become more concerned with wellness, for example, designers are looking more into areas of sport, hence the proliferation of athleisure. The same goes for eco-consciousness and sustainable fabrics.

"Everyone keeps wondering when this athleisure trend is going to go away," said Patel. "But designers are looking at how people are living their day-to-day lives. Before, you would only wear sneakers to the gym. And now you have sneakers for every aspect of your life."

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So, while some trends are still in one day and out the next, others have a longer shelf life if they're in sync with what we need, rather than what we want at any given moment.

Claire Distenfeld, the founder of Fivestory believes that because trends are coming from so many different sources today, that they're cycling at a slower rate than than in previous years.

"There’s a lot more surface area for them to stick," she said. "Meaning there are more outlets for people to see them. It’s almost a snowball effect: the trends get bigger and bigger, more widespread, and more sanctioned through all these different platforms." She used Millennial pink as an example of a trend that went from a small community of creatives to huge companies—and is still going strong.

It's for this same reason, though, that Bruce Pask, the men's fashion director at Bergdorf Goodman believes the opposite. "I think we cycle in and out of trends much more quickly than in the past simply because there is so much visual information out there constantly repopulating our feeds," he said. "There is a hunger for the new and the next."

Meanwhile, Patel stands somewhere in the middle, saying that there are two kinds of shoppers when it comes to following trends: "There are the fast fans who need something now, and then it’s gone tomorrow. And social media really feeds this immediacy. But then most runway needs more time to percolate to hit mainstream."

In other words, there are the trend obsessives Pask describes, who are on the frontlines responding immediately to the trends they see in their various feeds. And then there are the rest of us, who are just catching on to trends as others are discarding them.

In this way, we can perhaps all agree that trends are more ubiquitous and easily digestible in 2017, but as a result they're reaching different people at different times, meaning their cycle is more like crashing waves, rather than a bell curve.

Pask sees this with menswear, specifically. "Menswear trends or arcs, as we can say, definitely move at a more modified pace," he said in comparison to womenswear. "But it also depends upon which worlds we are examining. Are we looking at the broad world of menswear or are we pinpointing a fashion follower or early adopters?"

With wider, fuller trousers, for example, "early adopters" are catching on to the trend, which they saw on the recent men's runways, on Instagram, or in fashion publications. But it will take a little longer for this trend to reach the mainstream—if at all.

There is one aspect of trends, however, that is certainly cycling faster than ever before: nostalgia. It has always been the case with fashion that in time, what's old becomes new again—take the return of the '80s, for example. But as younger consumers become both more engaged and influential, trends of the past are returning more quickly. Currently, we're still in the 2000s, but we're already nostalgic about what Paris Hilton wore 10 years ago.

"I was excited and surprised to see the Juicy Couture tracksuit come back around with Vetements," said Patel of this phenomenon. "It’s coming back for a whole new generation to try."

Even if a trend is new to some eyes, though, designers can't simply just bring back the same looks of the past. Instead, each season they're challenged with the task of taking a trend and making it new and fresh. Then, it's up to the buyers to evolve with both designers and their customers.

With off-the-shoulder tops, for example, Distenfeld remembers posting a photo five years ago of one of Rosie Assoulin's looks, saying that it would be the next new trend.

“Now you need an off-the-shoulder top with ruffles," said Patel on the same subject. "Next you need one shoulder.”

While buyers and editors have always welcomed the task of giving consumers a gentle hand with evolving trends, consumers are now just as informed, and oftentimes know exactly what they want. When those crystal Saint Laurent boots walked the runway, for example, Patel said there was a waitlist for them the following day. It's not exactly "see now, buy now," but it's indicative of a culture in which trends are defined immediately.

"At Bergdorf Goodman, we often receive requests for pieces immediately after they've been seen worn on musicians," said Pask. "Take Drake's red Moncler parka, for example, or the printed silk Saint Laurent bomber Justin Bieber wore."

But at the same time, celebrities are also now styling themselves based on what they see young people or influencers doing on social media. So, instead of trends coming from top down in popular culture and like they used to, they're looping in an infinite figure-eight.

At what point do they stop, though? Do we ever say enough is enough anymore, or do trends snowball endlessly into the void?

“Over-exposure is a trend’s best friend, but also it’s worst enemy,” said Distenfeld. And with this, every buyer agreed. By definition, a trend is something that a collective of people are participating in, but in fashion, to be trendy is to be one step ahead of everyone else. It's for this reason that buyers often tire of a trend before the mainstream public, but eventually Millennials will grow out of pink and shoulders will get cold.

“It’s funny, because for me, ‘trend’ is actually the worst word," said Distenfeld. "It’s a way of saying, ‘This is a way to look like everyone else.’"

However, at the end of the day, Distenfeld also knows that the trend itself—or whatever you want to call it—will never go out of fashion. We haven't evolved that much, yet.

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