Y Combinator interviews only last ten minutes, so spending too much time explaining the basics of the company robs founders of precious time, Seibel explained. Put another way: If it takes too long to figure out what a business does, there will be less time to judge the viability of the business.

To help founders explain their companies better, Seibel offered a trick. ”Write two sentences about what you do, hand that to someone to read, and then, in their own words, let [them] explain to you what your company does,” he told founders. “If they can’t explain it, you are wrong, not them.”

Buzzwords and “start-up jargon” are a common problem. Founders often find it hard to explain their business simply because “they want to sound fancy,” Seibel said. The buzzwords “make it difficult for ordinary people to understand what a company actually does.”

Sondre Rasch, co-founder of Konsus, the first Norwegian start-up accepted into Y Combinator, made a similar point when he shared lessons learned during his time at the incubator in a blog post: “Use words people understand to convey what you do,” he wrote. “Get straight to the point.”

The Nigerian founders had some reason to listen closely to Seibel’s advice: Y Combinator has previously accepted Nigerian start-ups such Flutterwave, founded by Andela co-founder Iyin Aboyeji, and Paystack. Y Combinator built its sterling reputation in Silicon Valley by making very early-stage bets on start-ups that became multi-billion dollar names, including Dropbox, Airbnb, and Stripe. Seibel’s visit seems to send the message to local founders: If they can do it, you can too.

And Seibel’s visit served as further validation of the promise of Nigeria’s tech industry. Last month, Facebook CEO Mark Zuckerberg made a similar visit, touring tech companies in Lagos, including Andela, which closed a $24 million investment round led by the Chan Zuckerberg Initiative in June.

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