We know it when we see it … that uber-sexy eyeshadow quad, exorbitantly priced serum, or tech-y facial massager that we see on IG, at Sephora, or at the department store counter that immediately stokes the “I must have this right now” feeling. Products that we stalk on eBay because they sell out in five minutes flat.

But why do certain products generate cult-level devotion? And why do others die on the vine, failing to gain traction and generate revenue in line with expectations? What beauty marketer doesn’t want to crack this nut? Principally speaking, what does a product need to deliver to generate that “gotta-have-it” feeling? To answer this question, we set out to decode desirability in beauty.

To do this, me and my team of trend forecasting experts, many of whom are fashion designers by training, got together in our war room at LPK, armed with our must-have examples of the buzziest products and brands out there. When we emerged, we had a robust set of principles that brand managers, designers, and product developers alike can leverage today to create crave-worthy products that consumers simply cannot get enough of.

In particular, we took a deeper look at the fashion business, the original (and still best) architects of lust. They’re masters at marketing aspirational lifestyles, expressing the zeitgeist, speed to market, and creating burning desire. They innately understand trends. And smart beauty marketers draw on these tenets and translate them into products that sell.

Principle #1: Make it Scarce

The limited-edition concept thrives on a consumer’s desire for the unique: the opportunity to own something one-of-a-kind, special to only you, and made more urgent by the “buy now or never” nature of the transaction.

After launching her first makeup product back in 2015, Pat McGrath’s beauty line has been synonymous with “sold out.” With her small-batch products selling out in as little as six minutes and six seconds, McGrath, who has been quoted as saying, “scarcity breeds desire” has launched a 61-piece “Unlimited” collection in select Sephora stores. Last summer, she added the formerly limited-edition, sequin-laced Skin Fetish highlighting kits to the permanent Unlimited collection, much to consumers’ elation.

Principle #2: Make it Consumer-Obsessed

A deep understanding and respect for a targeted consumer drives loyalty, regardless of the medium. Brands successfully tackling this space listen first and do later, letting consumers deeply influence product development and other brand touchpoints.

Athletic-wear brand Outdoor Voices relies on consumer input for product innovation via social media with the hopes of cultivating greater loyalty from their customers—and they publicize it. “We said, ‘We’re building an assortment … tell us what your preferences are, what kind of support you need,’ and we folded that back into our product development,” CEO Tyler Haney was quoted as saying in Racked. “Now we’re launching the best six to eight pieces for OV’s customer.”

Principle #3: Make it Nostalgic

In a chaotic world, consumers find comfort and joy in familiar products and experiences reminiscent of simpler times and positive memories—re-lived in the here and now. We’ve seen this sentimental wave exhibit itself in particular among Millennials and Gen Z, who crave a taste of their 1980s and 1990s upbringings.

Cue GlamGlow and Hasbro, who teamed up last year to bring an adorable My Little Pony iteration of the beauty brand’s best selling GlitterMasks. Inspired by the magical ponies, the masks are colorful and sparkle-infused, transporting consumers to their imaginative childhood.

Principle #4: Make it Insta-genic

What makes a product Instagram-worthy? Those that bring to life their consumers’ “desired self” (online or IRL) and are beautifully designed to fit seamlessly into consumers’ curated, aspirational lifestyles. Gorgeous packaging helps consumers tangibly visualize their personal #goals and build their social currency among friends and followers.

Dirty Lemon, a line of water-based beauty tonics and detox elixirs that feature of-the-moment ingredients like charcoal and collagen, has gained a cult-like following thanks to Instagram and celebrity fans. Reinforcing its position as an “accessory to your daily routine,” the brand has partnered with Vogue to release a ginger-infused beverage bottled in a glittery, runway-ready vessel. Available exclusively via text, orders include a year-long subscription to Vogue.

Principle #5: Make it Democratic

No longer the antithesis of luxury, access and inclusion are more important than ever, especially when it comes to reaching new audiences and growing brand reach.

Chanel debuted its beauty assortment at select Ulta stores last year. The move makes iconic Chanel brand, which until now has only been sold in high-end department stores, more accessible to beauty shoppers, who can shop the more than 1,000 Ulta locations more easily than Sephora’s 430.

Principle #6: Make it Cute as Hell

Some products are just inexplicably squeal-worthy. Brands that capitalize on the desire for cuteness with instantly delightful aesthetics bring a sense of youthfulness and playfulness to the mundane.

No one understands this principle more innately than K-Beauty brands like Tony Moly and Too Cool For School. Not only are the products innovative, often playing up form and ingredients, but they’re also packaged with over-the-top cuteness playing on things like characters and food to up the joy factor with consumers.

Principle #7: Make it Rebellious

In a climate where status quo is no longer an option, brands use irreverence and unabashed defiance to create magnetic appeal that asserts their place “in the cool club.”

Beauty brand Lipslut encourages customers to “put their money where their mouth is” with irreverently named products that help make a statement in more way than one. Geared towards combating social and political injustice, 50% of all proceeds go to charities voted on by customers themselves. Their first product, Fck Trump lipstick, benefitted civil rights charities post-election in 2016, while more recently, the Fck Kavanagh lipstick donated 50% of all earnings towards anti-sexual assault organizations.

Principle #8: Make it Fast

As we all know, “Fast Beauty” is now a thing. As the number of brands in the beauty category swells, speed-to-market is crucial in satisfying consumers’ appetite for constant newness.

Despite growing competition, E.l.f. Cosmetics is reestablishing itself as the “fast beauty” pioneer by constantly churning out new items and getting them to shelves faster than ever before. The company’s production model includes twice-weekly innovation meetings that include everyone from executives to marketers to researchers, speeding up decision-making and maintaining an impressive speed-to-market time of just 22 weeks.

The beauty landscape has never been more crowded, fiercely competitive, or dynamic. Never has it been more imperative to make “gotta have it” a success criteria for new product launches slated for 2019.