No company is founded without a good dose of optimism. Your idea is a winner and you're going to make piles of money. But fast forward months or years and you may be looking at a plan that's not working out like you had hoped. Or, you might see a different opportunity that has the potential to be even bigger than what you're doing now.

Jessica Richman, cofounder and CEO of uBiome, a San Francisco startup funded by Andreesen Horowitz and Y Combinator, knows what it feels like. She met her cofounder when they were both founders of other startups and realized sequencing the DNA of the trillions of bacteria that live on and in humans could be huge. It turns out the microscopic organisms are correlated with dozens of health conditions–everything from irritable bowel syndrome and acne to mental health conditions such as depression and anxiety. Here are five clues she says indicate it's time to do something differently with your business.

1. You are deeply inspired in another area.

Richman studied math, computation and social science at Oxford, and computer science and economics at Stanford. While starting a company related to insights she garnered from her Ph.D. around social networks, she met her cofounder, Dr. Zachary Apte, who was finishing his Ph.D. in biophysics. The two started talking about how to change the world using genomic data. "So I got really inspired by that and I thought, 'This is fantastic. I can really do something more significant with the skills that I already have,'" she says.

2. You want to learn something new.

Not only was Richman interested in learning something new, she wanted the world to learn it, too. "We wanted to do something that had never been done, which was to gather this huge microbiome data set and generate value for suffering people," she says. "It was seeing if people in general could do this new thing."

3. You have a clear idea of your new customer.

In uBiome's case it was citizen scientists–regular people who dig science and like to learn about themselves and apply that knowledge to their own health and other people with similar interests. "There's this passion for science that is latent in the market and people want to be a part of it," she says. "This is a huge social trend that hasn't been uncovered yet."

4. Some other idea gets major traction.

Two and a half years ago Richman and Apte tried a little experiment. They hired a friend to make a video for $800, threw it on Indiegogo and sat back to see what would happen. The next thing they knew the crowdfunding platform had garnered $350,000 in just 10 weeks and The Associated Press was calling for an interview. It was the largest scientific campaign ever at the time and responsible for collecting microbiotic samples from 2,500 people–the largest study that's ever been done on the microbiome. "There was this moment of 'Wow. This is actually a big thing, in a way that we wanted but were totally unprepared for," she says. "So I think traction guides everything. If people want what you're doing they will let you know."

5. Experience guides you to a clear and different outcome.

You may not need to pivot your whole company, but rather decide what products to launch or tweak based on what you've learned over time.

"In our case we started off with consumers and citizen scientists, understanding the microbiome, and we found something in our data set that was really stunning and valuable," she says. "We [realized] we need to get our labs certified as a clinical lab and we really need to be able to provide tests to doctors and their patients. So that's what we did."