Second Time Around: Lessons from Serial Entrepreneurs Demitris Memos and Marios Stavropoulos

What drives a founder to build again after a successful exit? Is it the thrill of creation, the pull of an irresistible idea, or simply an inability to sit still? At Doers Summit 2025, Endeavor Entrepreneur Marios Stavropoulos (Softomotive, Ademu) and Demitris Memos (MarineTraffic, hoper), took the stage with our Managing Director Panagiotis Karampinis to share their journeys as second-time founders. Their conversation provided invaluable insights into what changes—and what doesn’t—when launching a company for the second time.

The Power of Experience

Both founders agreed: launching a second company is a completely different experience from the first. As first-time entrepreneurs, they had to navigate an overwhelming number of unknowns. The second time around, however, they found themselves more focused and deliberate in their approach.

For Demitris, three key takeaways from his first venture shaped his approach to hoper:

1. Intent & Clarity – Setting a clear vision and ensuring alignment across the team from day one.

2. Speed – Learning to move faster and make decisions more quickly, knowing that time is the most valuable resource.

3. Emotional Regulation – Mastering the rollercoaster of entrepreneurship and maintaining balance, both personally and for the team.

Marios echoed these sentiments, emphasizing that time away from Softomotive allowed him to see the bigger picture and recognize what he could improve. “Experience isn’t linear,” he noted. “It was only after stepping back that I could truly reflect on what worked and what didn’t.”

Why Build Again?

With successful exits behind them, why not just relax? Stavropoulos and Memos both admitted that the thought crossed their minds—briefly. But for them, the pull to create was too strong.

For Marios, the answer was simple: “I fell in love with an idea. I felt that it's something big and important that's worth my time.” His latest venture, Ademu, sits at the intersection of AI and human interaction, tackling challenges he believes will define the future.

Demitris, on the other hand, was drawn to hoper because of its transformative potential. hoper aims to make vertical mobility—via helicopters—more accessible, starting in Greece and expanding beyond. “Time is increasingly valuable, and we’re giving people back their time,” he explained.

Both founders also touched on the thrill of solving problems. “Happiness is all about solving problems,” Demitris said. “As an investor or advisor, you can point things out, but you’re not in the trenches solving them. I like the trenches more.”

The Challenges of a Second Time Founder

While experience is an asset, being a second-time founder comes with its own set of challenges. Expectations—both internal and external—loom larger. Demitris noted that people tend to assume past success means future success is guaranteed, which isn’t always the case. To combat this, he has structured his new venture to ensure internal accountability and external oversight, even setting up a formal board earlier than necessary. For Marios, the challenge is staying hungry. “Experience helps, but if you start thinking you know everything, it’s not going to work.”

What’s Next?

Both founders are at pivotal moments in their new ventures. hoper is gearing up for the summer season, refining its scheduled helicopter services, and scaling up operations. Ademu remains in stealth mode, but Marios promises something transformative in the AI space.

At Endeavor, we believe that serial entrepreneurs are key drivers of thriving ecosystems. Founders like Demitris and Marios don’t just build companies—they build momentum, creating a Multiplier Effect for others to take risks and create new ventures of their own.