Successful startups are like plane flights. The takeoff (developing an idea, building a team, raising funding, scaling, the inevitable pivot) and landing (getting acquired, going public, turning a profit) are, for many, the most fun parts, filled with adrenaline, tears, risk, and champagne.
Foursquare , on the other hand, is mid-flight. Unlike Facebook and Instagram--rockets careening toward space--Foursquare is on a path more like that of a commercial airliner, steadily climbing in elevation. Cofounder and CEO Dennis Crowley has grown the startup to 20 million users, 750,000 businesses, and 2 billion check-ins. These figures continue to grow, but it's not as if the startup is going gangbusters like Instagram or constantly swatting away billion-dollar or multi-billion-dollar offers like Facebook was years ago.
Today, one of Foursquare's earliest employees, business development head Tristan Walker , has bailed out, pulled his figurative ripcord, and left his self-described "dream job" to find the next thrill ride. "From day one, the opportunity at Foursquare enabled me to think big, take risks, reimagine what’s possible ... and following an incredible journey, I have decided to resign from Foursquare to pursue my next big dream," Walker wrote on his blog . He's since accepted an offer from Andreesen Horowtiz to become entrepreneur-in-residence, "a spot where I can work with a blank slate, people are encouraged to think big, and the opportunities are endless."
Only two months ago, Foursquare cofounder Naveen Selvadurai came to a similar conclusion. "After three years, I feel I've done all I can do, and I'm moving on," he wrote . "The Spring is time for things that are new, and I realize that I have a desire to do something new as well. I'm not sure about my exact next steps, but I'll probably get back to what I love most--being an entrepreneur, learning and building new things. Three years ago, we took an idea and threw it into the world. I'm going to miss the crazy intensity that is Foursquare, but am excited to see where it all goes from here."
To be sure, Foursquare has endured its share of turbulence--new funding rounds and valuations, opening a West Coast office, competition from Gowalla and Facebook Places, likely acquisition offers--but in its current state, the day-to-day direction is likely about putting your head down and building. It's clear this isn't about making a quick exit--Crowley seems to be in it for the long haul. This is about building revenue, expanding business partners, adding new features, growing its user base, and trying to maintain company culture while hiring employee after employee--characteristics and goals that are rare (and refreshing) in a world almost addicted to zero-revenue streams  and arbitrary valuations .
During this stage at many startups, it becomes clear who's better at running and optimizing businesses, and who's more interested in starting and inventing new businesses. Twitter cofounder Biz Stone placed himself in the latter category after he left the company in June of last year. "I've decided that the most effective use of my time is to get out of the way until I'm called upon to be of some specific use," Stone wrote , "So I can focus on new endeavors."
It was once said that Color and LaLa founder Bill Nguyen  was good at taking off and landing a company--but in between, "he needs a pilot," according to Redpoint Venture's Satish Dharmaraj.
Crowley has clearly been a good pilot for Foursquare. But that hasn't stopped Walker and Selvadurai from shopping for tickets for a different flight.
[Image: Flickr user Dr.Wendy Longo ]