Duolingo's first investors admitted they didn't believe in the education market, which they considered a bad business. They invested solely because founder Luis von Ahn had a previous successful exit to Google, demonstrating that a founder's track record can be more persuasive to early VCs than the business idea itself.

Counterintuitively, Duolingo discovered that competitive leaderboards are more engaging when users are pitted against strangers at a similar commitment level. Competing with friends often fails because their dedication rarely matches, making the competition feel unbalanced and demotivating.

For EdTech startups, pivoting from D2C to B2B school sales is challenging, with long sales cycles. However, it creates a stickier business not subject to seasonal dips and, more importantly, provides equitable access to students in underserved communities, not just affluent families.

Canva's core mission is a "two-step plan": 1) build a valuable company and 2) do good. Crucially, this isn't a sequential plan for after an exit. They believe step one fuels step two (and vice versa), integrating purpose directly into the business model from day one.

Founder Luis von Ahn states his biggest mistake was delaying monetization for nearly six years due to an early belief that "making money was evil." He estimates that if the company had started monetizing in year three instead of year six, it would be three years ahead of its current position today—a stark lesson for mission-driven founders.

Khan Academy developed a mission-aligned revenue model by partnering with The College Board, which pays them to create best-in-class SAT prep for free. This helps the Board fulfill its original mission of leveling the playing field while providing sustainable funding for the nonprofit, effectively funding its own disruption.

Instead of monetizing core communication, Club Penguin offered its heavily moderated (and costly) chat service for free. This ensured a safe environment for all children, not just those from wealthy families, aligning their business model with their core mission of universal safety.

To resist the temptation of for-profit spinoffs, Sal Khan frames his career choice as reverse philanthropy. He argues that had he stayed in finance and become a billionaire, he would have ultimately donated the money to an organization like Khan Academy anyway. This mindset allows him to bypass the wealth creation step and focus directly on the mission.