Slack

Pinterest

Slack

Slack uses a freemium model. The free tier gives you access to your most recent 90 days of messages and 10 app integrations.

That's enough to get hooked. Then Slack charges per user per month — $8.75/month for Pro, $15/month for Business+, and custom pricing for Enterprise Grid.

The beauty of the model is that one person signs up, invites their team, the team gets addicted, and suddenly the company is paying for 500 seats. It's a virus that charges rent.

Pinterest

Pinterest makes money through advertising — specifically through "Promoted Pins" that look nearly identical to organic content. This is the magic of Pinterest's business model: ads don't interrupt the experience because the experience IS discovering products and ideas.

A promoted pin for a kitchen knife set appears right alongside organic pins of kitchen designs. The user doesn't distinguish between "ad" and "content" because both serve the same purpose.

Shopping ads are the fastest-growing segment. Brands upload their product catalogs, Pinterest matches products to user searches and boards, and users can buy directly through the platform or click through to the retailer's site.

Pinterest gets paid per click or per thousand impressions.

Revenue reached $3.65 billion in 2024, up from $3.05 billion the year before, and 2024 was its first genuinely profitable year. Average revenue per user is growing but still well below Meta's — the upside is enormous if Pinterest can close that gap.

Slack

Stewart Butterfield had already done this exact thing once before. In 2002, he was building a massively multiplayer online game called Game Neverending.

The game flopped but one of its features — a photo-sharing tool — became Flickr, which Yahoo bought for $35 million in 2005.

So in 2009, Butterfield did it again. He started a company called Tiny Speck to build another game called Glitch — a quirky, non-violent MMO where players collaborated instead of fighting.

The game was beautiful, weird, and a complete commercial failure. It shut down in November 2012 after never finding a big enough audience.

But the internal communication tool the Glitch team had built for themselves was something special. They had created a searchable, organized messaging system because email was driving them insane.

Every conversation was in channels. Everything was searchable.

Files were shared inline. It was everything email should have been but wasn't.

Butterfield looked at this internal tool and thought: this is the actual product. In August 2013, Slack launched in preview.

Within 24 hours, 8,000 companies had signed up. Within two weeks, it was 15,000.

The growth was so fast that Butterfield said it felt like "trying to drink from a fire hose."

Pinterest

Ben Silbermann was a former Google ad operations employee who quit in 2008 to build apps. His first attempt was an iPhone app called Tote — essentially a mobile catalog that let women browse and bookmark products from fashion retailers.

Nobody downloaded it. But Silbermann noticed something in the data: users were saving products obsessively.

The collecting behavior was more interesting than the shopping behavior.

He teamed up with Paul Sciarra, a classmate from Yale, and Evan Sharp, a designer who was studying architecture at Columbia. Together they built Pinterest — a visual bookmarking tool that let people "pin" images from around the internet to organized boards.

Think of it as a digital mood board that anyone could make.

Pinterest launched as an invite-only beta in March 2010. Growth was painfully slow at first.

Silbermann personally wrote to the first 5,000 users, giving them his phone number and asking what they wanted. The early community was overwhelmingly women interested in home decor, fashion, recipes, and DIY projects.

By 2011, Time magazine named Pinterest one of the 50 best websites. By 2012, it was the fastest site in history to reach 10 million unique monthly visitors.

Slack

Slack grew almost entirely bottom-up. Nobody sold Slack to companies.

Employees adopted it on their own and then convinced their bosses to pay for it. One developer would start using the free version, invite their team, and within weeks the whole department was hooked.

IT departments would discover that half the company was already on Slack before anyone asked for approval.

The integrations strategy was genius. Slack made it dead simple for other software tools to plug into Slack.

Instead of checking Jira for bug reports, Salesforce for deals, and GitHub for code changes, everything pushed notifications into Slack. Slack became the operating system of work — the one app you kept open all day.

Word of mouth was the main growth driver. Slack didn't spend heavily on advertising early on.

They spent on making the product feel delightful. The loading messages were funny.

The emoji reactions were addictive. The search actually worked.

People genuinely liked using it, which is almost unheard of for enterprise software.

Pinterest

Pinterest grew organically through women sharing boards with each other. The weddings use case was the killer app — brides-to-be would create boards for dresses, venues, flowers, and invitations, then share them with their wedding parties.

That viral loop drove millions of signups.

SEO is the secret weapon. Pinterest pages rank extremely well in Google Image Search.

Someone searching "modern living room ideas" often sees Pinterest results on page one. That drives a large stream of organic traffic from people who were not looking for Pinterest at all.

Unlike other social platforms, which compete with Google for attention, Pinterest quietly benefits from it.

The shopping pivot has been the growth unlock. Under CEO Bill Ready (former Google and PayPal executive who took over in 2022), Pinterest aggressively invested in shopping features — catalog integrations, buyable pins, merchant verification, and visual search for products.

The thesis: Pinterest users are already in a shopping mindset, so removing friction between "I like this" and "I bought this" is the straightforward path to revenue growth.

Slack

Microsoft Teams was the existential threat. When Microsoft bundled Teams for free with Office 365 in 2017, Slack knew it was in trouble.

Microsoft had 300 million Office users who could start using Teams without paying anything extra. Slack even took out a full-page newspaper ad welcoming Microsoft to the chat market — a bravado move that masked genuine fear.

By 2020, Teams had overtaken Slack in daily active users purely on distribution.

The pandemic was a double-edged sword. Remote work exploded demand for Slack, but it also exploded demand for Teams, Zoom, and every other collaboration tool.

Slack's growth accelerated but so did everyone else's. The window where Slack was the obvious default was closing.

Revenue growth started slowing. After years of 50%+ annual growth, Slack's growth rate dropped to the low 30s by 2020.

Wall Street punished the stock, which dropped from its IPO price. The writing was on the wall — Slack couldn't outrun Microsoft alone.

In December 2020, Salesforce announced it was acquiring Slack for $27.7 billion. Butterfield stayed on as CEO until 2023, then left.

Pinterest

Pinterest's demographics are both an advantage and a limitation. The platform skews heavily female (over 60% women) and is strongest in home, fashion, food, and weddings.

Expanding beyond these categories to attract male users, younger demographics, and different use cases has been slow.

Competition for ad dollars is fierce. Pinterest competes with Meta, Google, TikTok, and Amazon for advertising budgets.

Most advertisers allocate the bulk of their spend to Meta and Google first, then consider others. Pinterest needs to prove its return on ad spend is competitive to win larger budget allocations.

Creator economy is underdeveloped. While Instagram, TikTok, and YouTube have massive creator ecosystems with monetization tools, Pinterest has historically been about content discovery, not content creation.

Users pin other people's content — the original creators often don't even know their work is on Pinterest. Building a creator program and driving original content creation on the platform has been a recent focus but lags far behind competitors.

Slack

Slack is the core messaging platform — channels for teams, direct messages, threads for focused discussion, and huddles for quick voice/video calls. Slack Connect lets you message people at other companies directly through Slack instead of email.

Slack Canvas is a built-in document editor for notes and wikis right inside channels. Workflow Builder lets non-technical users automate repetitive tasks without writing code.

The App Directory has 2,600+ integrations — connect Google Drive, Salesforce, Jira, GitHub, or basically any tool your company uses.

Pinterest

Pinterest Home Feed — the core discovery surface showing personalized pins based on user interests, boards, and search history. Pinterest Lens — visual search technology that lets users take a photo of any object and find similar items to buy on Pinterest.

Pinterest Shopping — integrated e-commerce allowing users to browse and purchase products directly from pins linked to retailer catalogs. Pinterest Boards — the organizing system where users save and categorize pins into collections, used for wedding planning, home renovation, recipes, fashion, and more.

Pinterest Shuffles — a collage-making app for Gen Z users to create aesthetic mood boards, driving younger user adoption.

Slack

Accel Partners, Andreessen Horowitz, Social Capital, GV (Google Ventures), SoftBank, Dragoneer Investment Group

Pinterest

Bessemer Venture Partners, FirstMark Capital, and Andreessen Horowitz were early investors. Fidelity and Valiant Capital participated in later rounds.

Rakuten invested strategically. The April 2019 IPO raised $1.4 billion at a $12.7 billion valuation.

Elliott Management, the activist investor, took a large stake in 2022 and pushed for operational improvements that contributed to the company's path to profitability.