Flickr co-founder Caterina Fake's newest start-up, Pinwheel, is an online platform on which users can tag a map of the world with personal stories, messages, and photos. I caught up with Fake for the May 2012 issue of Inc. Here's the rest of my interview with the serial entrepreneur:

How did you come up with the idea for Pinwheel?
One misconception is that start-ups start with a Eureka moment when the entrepreneur is sitting in the bathtub. It doesn't happen that way. For me, at least. I guess the idea's been evolving since 1999. I didn't realize that until my ex-husband and co-founder on Flickr called me to congratulate me on the launch, and he actually reminded me of a conversation we had in '99 about how cool it would be to be able to leave notes in places like doorways and street corners and various places around the world. Naturally, that didn't go anywhere. Back then it wasn't really possible. No one had smartphones. Nobody used geo-location, except the military. In the intervening 13 years, everything has changed. People have now been using GPS, checking in on Foursquare, and the other location-based services out there. There's a good amount of familiarity with using systems like this, which I think is indispensible in terms of technology adoption.

It stands to reason these location-based services would be used mostly on mobile devices, but you guys launched Pinwheel on the Web, instead of as an app. Why is that?
Content creation happens more easily on the Web. That's why we went out first with the website and don't have the native mobile app developed yet. Creating content is much easier online when you have a keyboard and a big screen. That being said, there is a mobile version you can use in a smartphone browser, and we have an Apple app in testing.

What content on Pinwheel is blowing your mind so far?
Someone at LinkedIn did this wonderful set of notes of all the locations of all LinkedIn's offices. I think they've had six or seven offices, the first one being Reid Hoffman's apartment. Subsequently there was a little office with five people here, then a bigger office with 20 people, there. So it's really wonderful uses that we hadn’t come up with or thought of ourselves, but our people come up with them. That’s what I love about it. There are infinite ways people could use it.

Be honest: Is it easier starting a business the third time around?
It has its advantages and disadvantages. It's much easier to raise money. If a start-up dies, the most frequent reason is it ran out of money, so being properly financed is really important. The disadvantage is expectations are high. Because of that, a lot of times entrepreneurs are afraid of taking risks as a second-time entrepreneur. People are afraid of losing what they've already gained, so they take fewer risks. That's not what you want to do when you're running a start-up; you want to embrace risk.

As an advisor and investor, you give plenty of of advice to other start-up entrepreneurs. What advice helped you with Pinwheel?
I always say it's the founding team that determines the culture of the company and how the product evolves, so hiring's one of the most important things you can do. We were very selective in terms of the people we brought on board. Hiring was really a challenge. One other thing I think is really important is, entrepreneurs need to start building today. The barrier to entry in tech is low, so start designing, start coding it, launch it, build prototypes, build a working version of it. The Internet has amazing powers of distribution. You can test your ideas. You can see if it works, if it doesn't work, whether it's fun, and whether you're sufficiently motivated. People who go into entrepreneurship to get rich aren't going to be happy. It’s the building of things that makes you happy. You have to enjoy the process whether you succeed or fail.