Hollywood’s annual awards season wrapped up this weekend with the 89th annual Academy Awards and one hell of a photo finish. But the dresses worn on the red carpet will live on forever, immortalized in a deluge of best-dressed lists.

At this time of year, it’s already tough to read any entertainment-related stories online without encountering a slideshow of celebrities in floor-sweeping swaths of sequins and lace. But the film industry’s most prestigious show tends to inspire big fashion gestures among Hollywood’s elite, resulting in the juiciest best-dressed lists of all.

The celebrities who end up on these lists typically have a lot in common; most are impossibly thin, and nearly all are clad in a swishy, floor-length gown. Certainly, they all look lovely.

But prettiness alone has never been enough to secure a spot on a top-tier best-dressed list (like the ones compiled by Vogue, Vanity Fair, and New York magazine). There are, and always have been, a flurry of factors that fashion editors consider when cherry-picking their champs. And while these factors have changed and evolved over the years, they’re currently as convoluted as ever.

The modern best-dressed list has become such an important facet of modern fashion criticism that it can affect actresses' careers

Fashion publicist Eleanor Lambert, who also founded the Council of Fashion Designers of America (CFDA), penned the first-ever major best-dressed list in 1940. Titled “The International Best-Dressed List,” her rundown of the globe’s best dressers ran until 2002, when she gave it to Vanity Fair, which now publishes it annually.

But by then scores of copycats had cropped up, along with a major magazine franchise built on the best-dressed conceit — People magazine’s Best & Worst Dressed issue, which exists to this day.

The most famous of Lambert’s successors was iconic fashion critic Richard Blackwell, known simply as Mr. Blackwell. The self-proclaimed “king of the caustic quote” added snark to the medium 1960, when he debuted his “Ten Worst-Dressed Women” list. The annual takedown, which would go on to call Julia Roberts “Godfather III in drag,” was the scourge of Hollywood starlets up through the 1990s.

Back then, these lists had heft, and were absolute. No chorus of social media players existed to challenge an editor’s picks or put forth alternatives.

The current glut of lists has all but zapped them of their novelty, not to mention impact. “With the democratization of fashion and the rise of social media and blogs, does what people at one fashion magazine say really matter?” asked Erin Weinger, a former digital style director at the Hollywood Reporter and current online editor at Vogue Australia.

Probably not. At least not to younger readers, who are more invested in their Instagram and Facebook feeds than in any single media outlet.

But scoring a spot on a well-read list can still be a very big deal for up-and-coming designers — whose alignment with a fashion star (say, a Rihanna or a Gwyneth Paltrow) can fast-track them into the mainstream. The lists are also important to celebrities who are vying for lucrative beauty, fashion, and accessories campaigns.

“For a young designer, a photo of a big celebrity in their design on a best-dressed list can be completely career-making,” says stylist and former Allure magazine fashion director Siobhan Bonnouvrier. “For [designers, the lists] definitely matter.”

And best-dressed lists can be critical cogs in the publicity machines designed to build and bolster a star’s brand equity. Meryl Streep doesn’t need to care about what we think of her shoes. But that’s not necessarily the case for rising stars like 2017 Oscar nominees Ruth Negga and Naomie Harris.

A great example of the financial heights a Hollywood newbie can scale, in large part through the image she projects at public events, is Lupita Nyong’o, who won the Best Supporting Actress Oscar in 2013 for 12 Years a Slave and later nabbed a beauty contract with Lancôme after a series of much-cooed-over red-carpet appearances. Nyong’o also forged a tight relationship with fashion house Prada, and was the face of the Prada sub-brand Miu Miu for a season (she wore a Prada gown to the 2014 Oscars).

Inclusion on a top-notch best-dressed list can not only smooth the path to brand ambassadorships — as it also did for Jennifer Lawrence, the current face of Dior — it can also play a small but significant role in creating better professional opportunities with studios and filmmakers. The impact of a dazzling red-carpet appearance can include increased media coverage and a surge in social media followers — both of which are keenly noted by casting agents and studios these days. The result can be a heightened, more bankable profile in Hollywood.

Almost all A-list celebrities work with Hollywood stylists

Nyong’o and Lawrence didn’t attain their red-carpet glory all on their own. Both actresses, along with just about every A-lister in Hollywood, work in close collaboration with stylists — professionals who are paid to create memorable head-to-toe looks for their clients. (Nyong’o works with stylist Michaela Erlinger; Lawrence is outfitted by Jill Lincoln and Jordan Johnson, former protégées of superstar stylist Rachel Zoe.)

During awards season, film studios often pay stylists to work with their awards contenders. That’s because the stakes are as high as ever when it comes to red-carpet dressing, and also because, in the age of high-definition screen grabs, nobody trusts actresses to dress themselves — not even the actresses.

Plus, working with a talented, well-connected stylist increases a star’s chances of landing on a best-dressed list. Gifted stylists — including vets like Elizabeth Stewart, who dresses Cate Blanchett and Jessica Chastain, and Erin Walsh, who outfits Sarah Jessica Parker and Maggie Gyllenhaal — know intrinsically how to create ensembles that walk the line between old-school glamour and youthful edginess, which so often seems to be the winning recipe for a memorable red-carpet look.

They’re exceptional at their jobs, so their clients tend to be among the most polished-looking players on the red carpet.

Established stylists are also in thick with the top design houses, so they have the advantage of being able to borrow red-carpet-ready looks from designers’ latest collections for their clients to wear — sometimes mere days after said looks are debuted on the runway. The couture shows now take place in Paris smack in the midst of awards season, “and the stylists are front-and-center selecting gowns for their clients, that often show up on carpets within days of a show,” notes Weinger.

When they gel, celeb-stylist relationships can also lead to brand deals, with designers and stylists working together to mold a star’s style persona before contracts are signed.

Of course, not all celebrity-stylist matchups result in best-dressed list victory. At the 2013 Oscars, stylist Rachel Zoe put Anne Hathaway in a pale pink Prada gown that highlighted the actress’s nipples in an odd way. Shortly after, Hathaway replaced Zoe with stylist Penny Lovell, who steered the actress’s style persona from goody-goody to hipster-prep.

But long-term collaboration with the right stylist can solidify a celebrity’s status as a fashion superstar. The Blanchet-Stewart relationship is a great example of this. By all reports, Blanchett is a lover of fashion, and certainly wears it well. But her work with Stewart, a former New York Times fashion editor, has put her at the top of best-dressed lists for the better part of a decade, and transformed her into a Hollywood style icon.

A celebrity who’s trending can take priority over one who’s not

Fashion editors are always working to earn a socially engaged readership, so they’re “looking at who would be garnering a lot of attention that evening, whether they’re nominated or are likely to receive an award,” says Bonnouvrier. “You’re also looking [to include] people who are very topical and hot at that moment.”

The practice of strategically including a brand that advertises on a website or in a magazine also happens. The scene in The Devil Wears Prada where Meryl Streep demands of her shell-shocked underlings, “Where are the advertisers?” during a fashion shoot run-through didn’t come from nowhere — it’s reflective of the realities of many modern media properties that have seen the journalistic “church and state” wall between editorial and advertising departments turn from solid rock to marshmallow, typically out of financial necessity.

Weinger notes, “When it comes to the web especially, best-dressed lists are definitely a way to fit in advertisers and designers who you honestly can’t fit a mention of anywhere else.”

But she added that creating a list that prioritizes popular web searches and celebrities with huge social followings — or celebrities who are trending in social media conversations — is even more important.

“If an actress happens to be trending on Google search and there’s nothing otherwise newsworthy to say about her, putting her in a best-dressed list can be a good way to get that click-bait in there,” Weinger says.

Bonnouvrier, too, has seen “a stronger correlation between editorial coverage and a celebrity’s social media following” in recent years. “These stars with massive followings — magazines can and do look to capitalize on that,” she says. “They benefit from featuring them.”

Some celebrities are universally understood to be stylish, so they transcend things like social media numbers

Like the rest of us, fashion editors have their favorite style stars — and they often highlight those stars in style roundups, whether they’re trending or not.

Diane Kruger, Carey Mulligan, Chloë Sevigny, Emma Stone, Sienna Miller, and Victoria Beckham are among the notables who consistently pop up on best-dressed lists. Kruger, in particular, is so beloved by fashion editors and so ubiquitous on best-dressed rundowns that her personal style tends to overshadow her work as an actress.

All of the celebs mentioned above tout a brand of personal style that, generally speaking, tends to downplay coquettishness in favor of less traditional feminine aesthetics.

“They have a little bit more of an intellectual interest in fashion than the typical celebrity,” says Melissa Magsaysay, a freelance fashion writer and brand consultant and former fashion editor for the Los Angeles Times. “They like fashion and they naturally dress in a way that goes a little bit against the grain. Without them, it’s just a lot of prettiness and excess on the red carpet. They keep things interesting.”

The designer a celebrity wears can impact her inclusion on best-dressed lists

Fashion editors know (or can easily find out from a star’s publicity team) who designed any gown that’s appeared on a red carpet. Armed with that information, they consider many questions, including, “Is the designer who made the gown a recognizable name, or is it or someone more obscure or low-end?” explains Bonnouvrier. “Also, a designer who is really hot or new might take priority over one who’s not. Or maybe a fashion house just got a new designer and that person is all the rage. If that’s the case, they will certainly get the coverage.”

A prime example of the right girl in the right dress — created by the designer du jour — would be Reese Witherspoon at the 2007 Golden Globes. The actress donned a short, canary-yellow strapless number custom-designed by Olivier Theyskens, who at the time had quite recently been named creative director of revived fashion house Nina Ricci. The total look was a smash, and made every best-dressed list that season.

All other things being equal, the success of a look comes down to styling

With few exceptions, women attending Hollywood awards shows all wear the same thing: a floor-length gown. The flattering, classic silhouette can, in its best iterations, evoke supreme elegance and drama.

But when two megastars, both equally beautiful and svelte, are standing side by side in near-identical gowns, what makes one a “best” pick and another not?

It typically comes down to the details, not the dress itself.

“It’s really all about the styling and hair and makeup choices in the end,” says Bonnouvrier, who added that successful styling “is all about balancing the proportions; if a dress is big and full, it needs accessories that work with that. Is the shoe a really strappy shoe, and does it work with a minimalist dress? Does that dress need a heavier, platform shoe? You really need to get the proportions right for the entire look to be successful.”

Beauty disasters are also the death of best-dressed dreams. Imperfect or “off” hair and makeup — think too-bold lips or too-high hair — can significantly demote a look. Case in point: In 2014, Angelina Jolie’s makeup artist used a powder on her face that reflected the flash of red-carpet photographers’ cameras, making her famous face look like a paint-by-numbers page in photos.

Playing it too safe with a gown and styling can also keep you off the best-dressed lists. The little black dress is great for a simple night out, but can feel lackluster on the red carpet next to so many brightly hued, dramatically cut gowns. While there are a few actresses who pull off simple, dark dresses beautifully — Jennifer Aniston immediately comes to mind — it’s not a particularly common approach.

When celebrities are forced to decide between a cutting-edge design and a timeless (but safer) gown, “It can be a ‘damned if they do, damned if they don’t’ proposition,” says Magsaysay. “They want to be a little daring and a little outside the box — everyone applauds that. But you can go too far either way. And you definitely don’t want to just bow out and show up in your black strapless dress looking like you’re going to your senior dance.”

How well a dress suits a celebrity's personality is as important as a gown's fit and cut

A good stylist won’t push her client too far beyond her comfort zone; stylists know that fashion editors and the general public like to see their favorite celebrities appear comfortable, confident, and looking like themselves — or at least like the public’s perception of who they are.

Take Tina Fey and Kristen Wiig — two Saturday Night Live alums with very different fashion personas. Fey favors Old Hollywood glamour, in the vein of bustier-topped strapless gowns. Conversely, Wiig takes quiet risks, opting for artfully loose silhouettes with tiered or ruffled elements, or formal pants. The clothes fit the personalities.

“A [successful] look should feel really authentic to the person wearing it,” says Bonnouvrier. “It should be an extension of a person’s persona and be very believable.” Because ultimately, “You should have the feeling that they could have put the look together themselves. Although everyone knows they didn’t.”