Crucially, though, Vardi said that luck also had a huge role to play in investing.
"I can't stress enough the importance of luck," he noted.
Indeed, when Vardi made his early investment in ICQ, he said he "didn't have any idea what was going on." He invested $75,000 in the messenger's parent company Mirabilis in 1996 after he was approached for funding by its founder, his then-26-year-old son Arik.
"I swear to you, when I gave the money, I thought it was ridiculous," said Vardi. "I thought: 'Who would want to speak on a messenger when they could talk on the phone?'"
The business "took the world by storm," however, and just 19 months later it was bought by AOL for $407 million.
"The most surprised people were ourselves," said Vardi, recalling how his son and Mirabilis' co-founders were initially taking bets on whether the company would even manage to secure 3,000 users.
At its peak, the messaging platform had 100 million registered accounts.
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