So it turns out that the emotional rollercoaster that “the PMARCA Guide to Startups” warned us about isn’t the only roller coaster entrepreneurs ride.

Of course that’s the one you think of first, “Tears,” where you experience your highest highs and lowest lows. Then there’s “Ride or Die,” the roller coaster serial entrepreneurs favor, alternating between frequent successes and failures. And then there’s “The MVP.”

Before reading Yevgeniy (Jim) Brikman’s Ycombinator post “A Minimum Viable Product is Not a Product, It’s a Process,” I didn’t realize what kind of ride I was about to get on. I thought it was more like a rocket launch. You get on, develop your minimum viable product, launch and continue your upward trajectory, adding and refining as you go. Boy was I wrong.

I thought I had a good grasp on the minimum viable product. I assumed that you eek out a “crappy version one made by a two-person startup [people’ve] never heard of,” like Paul Graham describes in his blog. Then you put it out and build from that foundation. No, Graham wasn’t talking about your minimum viable product at all. Your minimum viable product is an experiment designed to test your riskiest assumptions before you even begin designing and coding that rough version you built in your garage.

“The MVP” takes you over a series of super short, super fast peaks and valleys where you create, test and modify your latest minimum viable product. Then eventually, you launch.

I only saw the brilliance of AirBnB’s co-founder Joe Gebbia’s TED Talk after understanding the MVP concept. Essentially, he and his roommates’ first minimum viable product was hosting three strangers during a design conference. Before, I would have identified their crappy website inviting people to stay in their living room as their MVP. Now, I see they were testing their riskiest assumption— that strangers would host other strangers willing to stay in their houses.

Talk about stranger danger. But that’s what Gebbia was talking about. Everyone thought they were crazy, and for good reason. To find out if they were or weren’t, they needed to know whether or not people’s predisposition of wariness towards strangers could be overcome. They found out that it not only could, but that it could be fun and freeing. Gebbia said that one of creativity’s greatest functions was turning fear into fun.

They still had many rollercoaster hills to ride. They had to figure out if hosts would be willing to open their homes to strangers. They had to figure out if trust could be encouraged through design. They had to figure out how to match hosts with travelers. Each of these questions would become a fundamental assumption for their product, AirBnB. And it is worth it to test each assumption.

According to CB Insights, 42 percent of startups fail because there was no market need. These failed startups all failed to test their most critical assumption— that people actually want their product.

No one likes a slow roller coaster. Don’t spend your time developing a product only to be let down when you made an incorrect assumption, or two, or three. Enjoy the ride. Get on “The MVP,” buckle your harness and get ready for some steep hills. It’s best if you put your hands in the air and scream the whole time.