Uber

Sierra

Uber

Uber is a marketplace that connects riders with drivers. You request a ride through the app, the nearest driver accepts, picks you up, drops you off, and Uber takes a cut — typically 25-30% of the fare.

The driver keeps the rest. Uber doesn't own any cars.

They don't employ any drivers. They built a company worth well north of $150 billion by being the middleman with a really good app.

The model expanded into Uber Eats (food delivery, same concept — restaurants cook, drivers deliver, Uber takes a cut), Uber Freight (connecting truckers with shippers), and advertising. The advertising business is quietly enormous — Uber has data on where millions of people go every day, and brands will pay handsomely for that.

Sierra

Companies pay Sierra to run their customer service with AI agents instead of hiring rooms full of humans. The agent talks to your customers over chat.

It answers questions. It processes returns.

It updates subscriptions. Here is the clever part.

Sierra charges based on outcomes, not seats. Brands pay when the AI actually resolves a problem, not just for having the software installed.

That pricing is unusual. Most software charges a flat monthly fee no matter what.

Sierra only gets paid when the bot does the job.

Uber

The idea started in Paris in December 2008. Travis Kalanick and Garrett Camp were at the LeWeb tech conference and couldn't find a cab.

Camp had been obsessing over the idea of summoning a car with your phone. He bought the domain UberCab.com, built a prototype, and recruited Kalanick to help run it.

The first version launched in San Francisco in 2010 as a black car service — not the cheap rideshare everyone knows today. You'd tap a button, a Lincoln Town Car would show up, and it cost about 1.5x a regular taxi.

Ryan Graves answered a tweet from Kalanick looking for an "entrepreneurial product manager" and became employee number one. He ran operations while Kalanick was still finishing up another startup.

Graves would later become CEO briefly before handing the reins to Kalanick. The app launched with just a handful of cars in San Francisco.

It worked so well that riders couldn't shut up about it.

The real inflection point came in 2012 when they launched UberX — regular people driving their own cars at prices cheaper than taxis. That one decision turned Uber from a luxury black car service into a verb.

Within two years, UberX was available in hundreds of cities and the word "Uber" had entered the dictionary.

Sierra

Bret Taylor had already done the impossible twice. He co-created Google Maps.

He later became co-CEO of Salesforce, chaired Twitter's board during the messy Elon Musk takeover, and became chairman of OpenAI in late 2023. Clay Bavor spent 18 years at Google, most recently running its Labs group.

The two friends left their big jobs in 2023 to build something together. They picked customer service on purpose.

It is the least glamorous corner of software. Their logic was simple.

Companies hate their support costs. Customers hate waiting on hold.

AI that actually resolves problems could fix both sides at once. They launched Sierra in February 2024 with $110 million from Sequoia and Benchmark.

Uber

Uber's early growth strategy was beautifully ruthless. They'd roll into a new city, launch without asking permission, and deal with the regulatory fallout later.

Kalanick's stated version, which became known as Travis's Law, was that the product was so much better than a taxi that riders would defend its right to exist. In practice it meant launching first and arguing later.

The playbook was simple: launch in a new city, give massive discounts to riders (sometimes completely free rides), pay drivers signing bonuses and guaranteed hourly rates, and flood the zone until the city was hooked. Then slowly raise prices and cut driver incentives once the market was locked.

They burned billions doing this but it worked — by 2016 Uber was in 500+ cities across 70 countries.

They also weaponized word of mouth with referral codes. Every rider could give free rides to friends.

Every new driver got a bonus for signing up. The viral loop was insane.

At peak growth, Uber was adding a new city every day.

Sierra

Sierra went straight for big brands, not tiny startups. SoFi, Ramp, ADT, Sonos and Brex signed up early.

By 2026 it said more than 40% of the Fortune 50 were customers. The trick was trust.

Enterprises are terrified of an AI bot going rogue and insulting a customer. So Sierra built guardrails and let each company control exactly how the agent behaves.

Bret Taylor's contacts did the rest. When the chairman of OpenAI calls a Fortune 500 CEO, they pick up.

Sierra hit $100 million in annual recurring revenue in November 2025, seven quarters after launch, and $150 million by February 2026. In April 2026 it launched Ghostwriter, which builds and deploys a new agent from a plain-English description.

Uber

Where do you even start? Uber might have faced more simultaneous existential crises than any company in history.

Regulatory wars. Taxi unions, city governments, and entire countries tried to shut Uber down.

London revoked their license. France arrested two executives.

Uber was banned, unbanned, re-banned, and sued in dozens of jurisdictions simultaneously.

The toxic culture. In 2017, former engineer Susan Fowler published a blog post describing rampant sexual harassment, discrimination, and HR cover-ups at Uber.

It went nuclear. Investigation after investigation followed.

Board members resigned. Executives were fired.

Travis Kalanick's ouster. After the culture scandals, a leaked video of him berating an Uber driver, and a federal investigation into stolen trade secrets from Google's self-driving car unit Waymo, the board forced Kalanick to resign as CEO in June 2017.

Dara Khosrowshahi came in from Expedia to clean things up.

The cash burn was legendary. Uber lost $8.5 billion in 2019 alone.

They subsidized rides so heavily that riders were paying less than the actual cost of the trip. The company did not turn its first operating profit until the second quarter of 2023 — fourteen years after it was founded.

Sierra

Everyone is building AI customer service agents right now. Decagon has raised at a multi-billion valuation.

Salesforce, ServiceNow and Intercom all shipped their own agents. Sierra is not the cheap option.

It sells premium AI to giant companies that move slowly. The bigger risk sits underneath the product.

Sierra does not make its own AI models. It rents them from providers like OpenAI and Anthropic.

If those model makers decide to compete directly, Sierra's edge gets thin fast, and its co-founder chairing one of them only makes that question louder. A $15.8 billion valuation on roughly $150 million in revenue leaves almost no room for a stumble.

Uber

Uber Rides is the core product — get from A to B in someone else's car. UberX is the standard option, Uber Black is the premium black car tier, UberXL fits bigger groups, and Uber Reserve lets you schedule rides in advance.

Uber Eats is the food delivery arm and competes directly with DoorDash and Grubhub. Uber Freight is the logistics play — basically Uber for semi-trucks, connecting carriers with shippers.

Uber for Business lets companies manage employee rides and meals. Uber now also offers package delivery, grocery delivery, and even boat rides in some cities.

Sierra

The core product is the Sierra AI agent. It is a branded customer service bot that companies deploy on their website, app, and phone lines.

It handles the boring stuff. Order tracking.

Refunds. Password resets.

Account changes. Sierra also built its own tools to test and monitor these agents so they do not make things up.

In 2024 the company added a voice version that talks to customers on the phone. In April 2026 it added Ghostwriter, a tool that builds and deploys a new agent from a plain-English description.

The whole pitch is one AI agent that carries your brand's name and never sleeps.

Uber

Benchmark Capital, First Round Capital, Menlo Ventures, Jeff Bezos, Goldman Sachs, Google Ventures, Saudi Arabia's Public Investment Fund, SoftBank, Toyota, PayPal co-founder Peter Thiel, Tencent

Sierra

Sequoia Capital and Benchmark wrote the first checks at launch in February 2024, $110 million between them. Greenoaks Capital then led both the $175 million round in 2024 and the $350 million round in September 2025.

In May 2026 Tiger Global and Google's GV led a $950 million round at a $15.8 billion valuation, with Benchmark, Sequoia and Greenoaks back in. That takes total funding to about $1.6 billion.

That is partly the product and partly Bret Taylor. Investors bet on founders who have already built billion-dollar things.