When Kaivalya Vohra wanted to drop out of Stanford University to run his startup, it took "a couple of long conversations" to convince his parents.
But bringing them on board wasn't too difficult, he said.
"They saw how this business was growing in front of them, they saw how quickly we achieved what we achieved."
It took just nine months for Vohra and his co-founder, Aadit Palicha, to bring Zepto — an app from India that promises to deliver groceries in less than 10 minutes — to a valuation of $900 million.
Going in with the mindset that you're wrong and learning where to get right … that journey has been humbling.Aadit PalichaCo-founder and CEO, Zepto
How did two teenagers build one of India's fastest-growing quick commerce apps? CNBC Make It finds out.
1. Talk to customers
Finding a good product-market fit is important, said Vohra. His advice on how to do that?
"Speak to customers. Just use that as a holy grail [to] ensure you're on the right track to finding product market fit."
"One of the hardest things is actually getting to that point where you have a product that people love … It is much easier and much faster if you're constantly speaking to customers, getting feedback from them and learning from them," he added.
In the early days of Zepto, the 19-year-olds handled customer support themselves and delivered groceries to consumers just so that they could have a quick chat with them.
"We still do it till this day … We've got millions of customers, with hundreds of thousands of orders every day. [We still] spend a significant amount of time just speaking to customers, learning from them," said Palicha.
"Going in with the mindset that you're wrong and learning where to get right … that journey has been humbling."
2. Fall in love with your product
Palicha and Vohra weren't always taken seriously — not just because of their age, but also because of the "craziness" of an under-10 minutes delivery idea.
"When we started this 12 months ago, every conversation we had was, 'You're totally out of your mind, this is never going to work,'" said Palicha.
But their conviction in their product kept them going.
"Kaivalya and I fell in love with the product so much that we just saw ourselves as custodians of what would probably end up being a large phenomenon in consumer internet in India," said Palicha.
"If we don't build it, somebody else will. When you operate with that mentality, everything becomes less intimidating."
Falling in love with the product and building that conviction really just pushes you to … see that product through.Aadit PalichaCo-founder and CEO, Zepto
That's why the duo could take on "challenging conversations" with investors, senior executives, and even a government official, Palicha added.
Despite being just one of many businesses to join the instant commerce wave, it has caught the attention of investors. Its latest cash injection of $200 million in May brought Zepto one step closer to unicorn status.
"Falling in love with the product and building that conviction really just pushes you to … see that product through," said Palicha.
3. Be accountable
Palicha and Vohra have been friends since they were seven-year-olds — a major advantage as they turned from childhood pals to business partners.
"Kaivalya and I really complement each other's skill set. He has always been more technically sound than I am, so he's made a great chief technology officer," said Palicha.
"12 months ago, when we were building the first iteration of the product, I don't think we'd been able to get it off the ground [without him]."
For Vohra, it's their ability to "hold each other accountable" that brought them this far.
"This has been something we've been doing since way back … [even as] we worked on a bunch of projects together throughout school," he added.
"Over time, I think that relationship just strengthened. So yeah, it's a lot of fun."
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