If you want to get a sense of the insane speed at which things happen in Silicon Valley these days, you could pick one of the really prominent examples: Uber, say, which had no particular profile in 2011, yet in June this year was valued at a comical $18bn. Or you could pick one of many stories such as Leo Seigal’s. Seigal is a British entrepreneur who came to San Francisco halfway through a languages degree at Oxford. He let the university believe he was heading to France for his study year abroad; moved back in with his parents in London instead; co-founded a startup that helps celebrities run charity auctions online; then moved it to the US west coast. He’s now on his second company, Represent, a service allowing users to create branded merchandise online, which employs 26 people and has attracted more than $1m in venture capital funding. He tells stories of forging business relationships with everyone from One Direction to George RR Martin, and makes pronouncements like an exhausted veteran: “Honestly,” he told me recently, squinting against the sun on the rooftop terrace of his LA offices, “if I’d known how hard it would really be, back then, I don’t know if I would have done it.” Seigal, it probably ought to be clarified, is 23 – “and a half,” he adds. “Back then” refers to his arrival in Silicon Valley – which was at the beginning of last year.

There has never been an economy quite like that of west coast tech startups in 2014: no environment in which it’s been so easy for the right kind of person, with the right kind of idea, to go from nobody to worth millions in weeks, their app downloaded to a million smartphones. The results, as it’s often been noted, aren’t always that inspiring: an awful lot of companies seem to exist to solve the minor problems of privileged twentysomethings, such as ordering a takeaway more efficiently, or just to undertake actively cynical profiteering: there’s an app that sells restaurant reservations to the highest bidder. Still, there’s something undeniably intoxicating about eavesdropping on the excited conversations taking place in Blue Bottle Coffee, or the deals being discussed in Mission Dolores Park (provided you can dodge the guy taking his drone for a walk). This pregnant sense of possibility is what prompts more than 13,000 people to migrate each year to Silicon Valley, from across America and the rest of the world. And it is what motivates a small but apparently increasing number of British people, each year, to abandon their plans for university, get on a plane, find an apartment-share, struggle with the ceaseless hassles of getting the right visa – and begin doing what the would-be billionaires of Silicon Valley do all the time, even when they’re not at work, which is work.

“It’s the craziest thing, being out here,” Seigal says, sounding slightly astonished. He is wearing deck shoes, sporting a few days of stubble, and has just expressed his annoyance that his companies have finally hired an employee younger than him. “In most regular professions, I feel like it takes 10, 20 years to rise up, whereas we went from nobodies, who no one wanted to meet, to within a year, you’ve got such-and-such a celebrity [on board], and everyone’s suddenly interested. I’ve got friends who go into the entertainment industry, working in the mailroom, and now we’re working with their bosses.”

The idea for his first startup, Prizeo, came from conducting charity auctions at university, specifically one involving Jeremy Clarkson. A wealthy Top Gear fan at an auction might bid thousands of pounds to go racetrack driving with Clarkson, Seigal realised, but a smartphone-based raffle system could raise far more cash by selling a shot at winning to far more people for a smaller amount, such as £5. (Prizeo profits by taking a percentage of funds raised.) A successful collaboration with Jamie Oliver caught the attention of investors; later, the creator of Game Of Thrones accompanied one raffle-winner on a helicopter trip to a wolf sanctuary.

“It’s ridiculous,” Seigal says. “I mean, I’m not easily starstruck, but when you’re emailing personally back and forth with George RR Martin…” Not that this was necessarily his most pinch-yourself moment. That came “when we went to meet our friend at Facebook, and it was really late at night, and there was no one else there – except Mark Zuckerberg. And we were, like, oh my God.”

People have been trying to become internet multimillionaires in Silicon Valley for two decades now, of course; but in the last six or seven years, something’s changed. Any one person’s shot at success is still a question of very long odds and huge luck. But the process of trying to discover the next Zuckerberg, or the next Twitter, has been systematised: the Valley has become a Darwinian machine for vacuuming up youngsters, giving them just enough cash to test their ideas, then injecting massive quantities of money into a handful of victors in an effort to force the birth of an Uber or Airbnb every year or so. At the heart of this system is the startup incubator Y Combinator, founded by the British investor Paul Graham and based near Google’s headquarters in Mountain View. Twice a year, in winter and summer, it accepts about 60 small teams, writes them each a $120,000 cheque in return for roughly a 7% stake in future earnings, then gives them three months – sharing apartments nearby, working every hour of every day – to build their projects. (During the selection process, Graham reportedly asks each team: “What’s your long-term plan to take over the world?”) The event at the end of this period, “Demo Day”, a Dragons’ Den-style event in which each company showcases its work to the region’s leading investors, has become the stuff of legend.

“It was incredibly stressful,” says Seigal, who was admitted to Y Combinator last year. “But at the same time, it was a haven. Especially coming from London, where you feel really abnormal – here you’re praised as what it’s all about. It felt like we could do what we were doing without being asked questions. It’s just accepted that we’d like to become multimillionaires, and that we might have a shot at it.” Like other British founders in the US, he strives to be diplomatic about “Silicon Roundabout”, London’s rival technology cluster. But he can’t conceal his feeling that the west coast is where it’s at. Things move too slowly in the UK (“I’ve always been obsessed with doing as much as possible as young as possible – I’m just extremely impatient”) and it is harder to get funding. “I don’t want to be too harsh on London, because I’d like to encourage people,” Seigal says. “But at the end of the day, the benchmark for success for companies is Silicon Valley: how quickly can you get there?”

Not every British founder is so eager to get to the west coast as quickly as possible. Robyn Exton, the founder of Dattch, a dating app for gay and bisexual women, loved the atmosphere in London in her company’s earliest days. (Again, we’re talking the last couple of years.) “It was just so supportive,” says the 28-year-old, who grew up in Kent. They were supportive partly because “everyone was really desperate for there to be some big success stories”. Exton raised funds by working at a pub near her home in Hoxton, then was accepted to Wayra, the startup incubator backed by the Spanish firm Telefónica, and then raised £100,000 in investment. Her goal was to establish that there was space in the market for a dating network aimed exclusively at women. “The way the female brain processes information, the things women are looking for, it’s so different,” she argues. Accordingly, Dattch emphasises certain features more than other dating apps, such as messaging (“Women want to talk so much more than men do before meeting up in person”) and downplays others, such as geolocation, because there’s less interest in impromptu hook-ups. But now that the network has launched in six American cities, Exton is shifting her focus, too; she spends half her time in the US and expects she’ll spend more. Silicon Valley’s magnetic force can be resisted for only so long.

The Valley’s way of seeking the Next Big Thing naturally rewards a certain kind of person: ambitious, most often male, usually from a comfortable background and with sufficiently few attachments to drop everything and come to the Bay Area. One result is that the age of participants in schemes such as Y Combinator seems always to be falling; the year before last, west coast venture capitalists told Reuters they were funding more chief executives under 21 years old than ever before. “At a certain point,” the investor and Netscape founder Marc Andreessen was quoted as saying, “they can’t get much younger, or we’re going to be invested in preschool.” Peter Thiel, co-founder of PayPal and a well-known libertarian (he’s supported schemes for floating cities at sea, out of reach of tax authorities) has become the leader of a movement actively encouraging potential founders to jettison university and focus on business instead. This June, his foundation announced the latest batch of Thiel Fellows, 20 young people aged between 17 and 20, who’ll each receive $100,000 over two years for projects ranging from “accelerating how we learn” to curing cancer, providing they skip higher education.

A strange consequence of all this is a surreal kind of ageism that views those in their late 20s as getting dangerously close to being past it: 32 is “the cutoff in investors’ heads”, Graham has said. (“I feel like I have maybe 15 years,” Seigal tells me; as with the other founders I speak to, the question of where he might end up beyond that seems too abstract to make much sense.) Earlier this year, a report in the New Republic noted that Valley-area cosmetic surgeons were doing good business giving botox injections to men in their 30s and 40s.

***

“Every generation that came before us had to make a choice in life between pursuing a steady career and pursuing wild adventures,” Po Bronson wrote in The Nudist On The Late Shift, his chronicle of the first dotcom bubble of the mid-90s. “In Silicon Valley, that trade-off has been recircuited. By injecting mindboggling amounts of risk into the stodgy domain of grey-suited business, young people no longer have to choose… More happens here and so quickly, satisfying anybody’s craving for newness. In six months, you might get a job, be laid off, start a company, sell it, become a consultant, and then, who knows?” Bronson’s book is a vivid, manic account of trying to make it at the epicentre of tech, yet in places it feels oddly nostalgic: some of his fresh-faced pioneers are almost 30, and their $1,400 monthly apartment rentals wouldn’t get you much in San Francisco today.

Josh Buckley has no memory of the boom Bronson describes: he’d only recently learned to walk at the time. Now 22, the chief executive of the smartphone gaming company MinoMonsters is the epitome of the youthful founder trend: at 16, he was a pupil at a state school in Maidstone; by 18, he’d been accepted to Y Combinator; within weeks of finishing, he’d raised $2m dollars in funding. Not that he was inexperienced, exactly: he’d been designing websites for cash since the age of 11, and at 15 surprised his parents by emerging from his bedroom one evening to inform them that he’d sold, for a six-figure sum, a games community they didn’t even know he was running. (The family’s income came from his father’s property business; the web wasn’t part of their equation. “They were shocked,” he recalls. “I just went to bed.”) He laughs when you ask about the first computer he ever owned, because it ran Windows 95.

“There I am in Kent, going to school, and being bored, and then you’re dropped into this pool of the 50 smartest people in the world,” Buckley says, recalling his first days at Y Combinator. He talks so rapidly, he can occasionally be hard to understand, like a cliche of someone unwilling to lose a moment. “And I’m, like, holy shit! These people are so smart. Since I’ve been here I’ve constantly had that feeling: I’ve got to get better, I’ve got to get better. It makes you insecure. But you might as well take the productive reaction to it.” The productive reaction, in Buckley’s case, was “a secret new world of lovable pet monsters”, now with 7 million users, that evokes how Pokémon might look on your iPhone had Nintendo not taken the perverse decision largely to spurn smartphones. His offices, and the apartment he shares, with fellow co-founder Sasha MacKinnon, are in the same luxury building in downtown San Francisco, minimising the time he needs to spend neither working nor sleeping; there’s a spa pool on his roof terrace, and a hair salon and fitness centre in the building. Jack Dorsey, the hero-worshipped co-founder of Twitter, used to be a neighbour. In another hallmark of San Francisco today, the building overlooks a courtyard in which homeless people shout for money at passersby.

Buckley is disarmingly upfront about his ambitions: his “first goal”, he explains, is to run the biggest games company in the world; the ultimate rivals he thinks about aren’t fellow app designers so much as Disney. His driving motivation is a typical one: the urge to test himself personally against the best possible competitors – so that success, if it happened, would mean more. “I’d feel frustrated if I was just comparing myself to a small pool of people in England. Here you’re not just comparing yourself to other people in Silicon Valley. This is the best in the world. Right here.” If you win, you really win; you don’t need to wonder if the victory was somehow only partial.

What about the potential for a huge payday? Actually, Buckley says, money can only motivate so much: “You’re surrounded by billionaires, and you realise – these people’s lives are no better than mine. I have friends who buy Ferraris and McLarens, and they don’t even have time to drive them. Well, if that’s what being a billionaire gets you…” Besides – this is a refrain I hear from almost everyone I speak to – “starting up is hard. I can’t even tell you how hard it is to run a company here, let alone make it a successful one,” Buckley says, earnestly. “It’s just genuinely not worth doing it just for the money.”

Exton’s account of “starting up” – teaching herself to code in her spare time while working at the pub, tolerating baffling statements from potential investors (“You can’t possibly be a lesbian, you’ve got long hair”), whittling sleep down to five or six hours a night, and not even having a co-founder to commiserate with – hardly sounds like unbroken fun, either. You need a solid motive to keep going. Among other things, Exton considers her potential users: “Imagine a woman who’s only just realised she’s gay, and is living in a village in Wyoming, and has absolutely no way to meet other gay women, who doesn’t understand what she’s supposed to do, where she’s supposed to go.” A well-designed app can make a real difference to real people’s lives.

I wonder if Buckley ever thinks he should have gone to university instead, but the question registers only as a familiar kind he’s been asked by other oldsters. “Oh, you mean am I missing out on my youth and stuff? I thought that at some points.” His parents, initially hostile to his plans, sound amiably baffled by their son’s success: “They came out here once. They’re proud, I guess. But I think it might be hard for them to understand. I’ll call them every week, and sometimes I’ll have been banging my head against a wall, and they’ll say, why are you working these 18-hour days, why can’t you just be yourself? But then I’ll call them up one day and say, oh, I just raised $2m – that’s why I was doing the 18-hour days. I think they were quite impressed by that.”

***

For all the talk of “changing the world”, there’s a distinct sense that many of the highest-profile startups – if not necessarily the recipients of the most money – deal largely in trivia, the kind of thing that might lead a visiting Martian to conclude that the most exciting phase of innovation had been and gone. Making it easier for people to call a cab or rent out a spare room isn’t exactly revolutionary; nor is enabling people to send the message “Yo!” to each other’s mobile phones. Washboard, which promised to mail 25-cent coins, at a mark-up, for people to use in the coin-operated washing machines in their apartment buildings, might have been little more than a website launched partly in jest – but it made a certain point.

The reasons for this are partly technological. At this point in the web’s evolution, we’re mainly just working through the implications of everyone having a broadband-connected phone in their pocket, so the easiest way to launch a new idea is to locate some mild annoyance of daily life and use smartphones to smooth it out. The explanation is also financial: to find the next breakout firm, investors would rather bestow multiple small sums around a large number of startups, whose ideas can be swiftly developed with a few months’ coding – which biases them in favour of lightweight ideas, not tackling big social problems. Harj Taggar, a British entrepreneur, former partner at Y Combinator and, at 29, now a relative Valley geriatric, tells me that, “The whole culture now revolves entirely around these outliers, these once-in-a‑decade companies” such as Uber, Airbnb and Dropbox, which rise from nothing to dominating their industries within months. “There’s this expectation now that every year there’s going to be one of these outlier companies.” The latest is Stripe, set up by two Irish brothers, Patrick and John Collison, which recently raised funds that valued it at $1.75bn. (Its big selling point is that it vastly simplifies the usually complex and annoying process of accepting credit card payments online.)

This accelerated culture may also help portray startup life as a world unmoored from values, as if people are simply moving too fast to stop to think about the ethical implications of what they’re doing. Y Combinator’s motto is “make something people want”, reflecting the consensus that if there’s a market for something, it’s worth doing. Hence controversial services such as MonkeyParking, which lets drivers sell parking spaces they’re currently parked in to others who want them; or ReservationHop, which sells restaurant bookings the company has previously made. “Is this even legal? Is it ethical?” founder Brian Mayer wondered aloud after his product raised an outcry. “To be honest, I haven’t spent a lot of time thinking through these questions. I built this site as an experiment in consumer demand.” (Executives at Whisper, the anonymous messaging app, seemed similarly startled by the response to the Guardian’s revelations about their tracking of users.) The helter-skelter pursuit of consumer demand may also help fuel the Valley’s poor record on sexual harassment, and an atmosphere that can be more generally hostile to women. “There’s this freewheeling libertarianism that allows a lot of things,” Elissa Shevinsky, a founder of the dating app Glimpse, told Businessweek magazine earlier this year. She quoted a startup lawyer who told her “that startups are a [human resources] disaster. They violate a whole lot of laws” – especially concerning discrimination in hiring practices, it was implied – “and that’s overlooked”. Indeed, it’s taken to be “a good thing, because otherwise those companies couldn’t go to the next level”.

Exton says she’s “never experienced conscious, overt sexism”, though she adds that this might be because her app is explicitly aimed at women. (It would take an especially oafish potential investor to question her suitability for her role on gender grounds.) Still, “angel investment”, the early financial injections on which startups rely, is a personal business, Exton says; people tend to invest in companies whose goals have some “personal resonance” – and very few of them are women. Bewildered potential investors have told her they find the entire concept of a lesbian app “bizarre”; only with Dattch’s growth across the US and UK have they begun to be persuaded that there might be something to it.

And despite the widespread insistence that meritocracy prevails, privilege of various kinds still counts for a lot. “I couldn’t imagine being able to do this if I wasn’t from a privileged background,” says Seigal, who relied on a supportive family, an allowance from his parents, and the family home. “Not to take away from what I’ve done, because the vast majority of my privileged friends haven’t done startups. But most people just can’t afford to.” That said, being British, in this febrile atmosphere, can be a mixed blessing. On the one hand, the accent means people just assume you’re intelligent: “I think I’d have been sent home a lot longer ago if I didn’t have it,” says Taggar. On the other, a kneejerk tendency toward self-deprecation can be a disaster when you’re sitting opposite billionaire venture capitalists, trying to explain why you’re worth their money. “The best-case scenario is that they realise you’re joking, but they just think you’re odd for joking,” Taggar says. “The worst-case scenario is that they think you’re being serious: ‘Well, if he says he’s not very smart, then he must not be very smart…’”

Perhaps the hardest thing for Brits in Silicon Valley is something that’s hard for everyone: the sheer effort involved in maintaining the facade that everything is going great, business-wise, all the time. In fact, near-constant failure is fundamental to how the place works: for every superstar, there are hundreds that go nowhere by definition. Yet “you go to these startup events, and it’s the weirdest thing,” says Buckley, over coffee just outside his building. “‘How’s it going?’ Everyone’s, like, ‘Killing it, man! Killing it!’ It’s so frustrating.” You have to do it, because “you don’t want investors thinking, ‘Oh, what’s going wrong?’ It’s a very small community – word gets around, and people talk. So you can’t really say, ‘Oh, dude, it’s so bad.’” But the truth is that “every startup’s a mess on the inside, in its own different way”.

The 22-year-old sighs, briefly reflective, then resumes his fidgety, rapid-fire conversation – politely willing to keep talking to me, but eager to get back to the important business of becoming dominant in the world’s most competitive technology hothouse. He might succeed or fail, but he will never have to regret not having tried.

Day in the life: Robyn Exton of Dattch

Photograph: John Lee

6am Get up, straight out to a breakfast meeting, usually around Old Street.

8am Get to the office (Saturdays are my day off but I’ll most likely head in on Sunday).

9am Catch up on all updates from the San Francisco office; we use some amazing tools, so we’re always in sync with what everyone is up to.

10am Meeting with advisers to the business, to plan for challenges coming up.

12pm Lunch session with users, testing new features for the app and learning more about how we can improve the product for them.

Afternoon Blocked off for focused work, sound-reducing headphones on.

5pm Call with San Francisco office to plan for their day and let them know what we’ve been up to. We have a video stream always open, so we can chat into the evening as their day gets started.

7pm Leave the office.

8pm Dinner with an investor.

11.30-midnight Back home to bed (six hours’ sleep is fine, but not five).

Josh Buckley of MinoMonsters

Photograph: John Lee

7.15am Wake up, go on a 5km run along the San Francisco pier (I try to do this three times a week).

8.15am Shower, grab breakfast and check email.

9am Head to the office and meet with an investor.

10am Leadership team meeting, check in on product status.

11am Call with our licensing agent in London.

12pm Lunch with team.

1pm Meeting with interview candidate at coffee shop.

2pm Drive to Palo Alto for meeting with investor.

4pm Meet with marketing team to set up new campaigns.

5pm Catch up on email and finish any outstanding tasks.

7pm Head to the gym (luckily in the same building!).

7.45pm Go to dinner with a friend.

9pm Go to a social mixer hosted by one of our investors.

10pm Go home and read for an hour.

11pm Bed.

Leo Seigal of Represent

Photograph: John Lee

7am Wake up.

10am Return from Santa Fe where I had organized a cheque presentation ceremony for George RR Martin.

10.30am Brainstorming with staff for our growing merchandise platform represent.com.

11am-1pm Email, lunch in the office.

2pm Call with our chief operations officer in London, before he goes to bed.

3.30pm Talking with the customer service team.

4pm-5pm More email.

7.30pm Leave office, go to Mexican restaurant to say goodbye to an employee returning to the London office.

12.30am Bed.

This article was amended on November 14 to correct factual errors about Josh Buckley’s business