Early this year, the giant Japanese ecommerce company Rakuten led a $530 million round of funding in the ride hailing startup Lyft.

Today on stage at Business Insider's IGNITION conference, CEO Hiroshi "Mickey" Mikitani told the crowd why he chose Lyft instead of Uber.

The short answer: He passed up the chance to invest in Uber early, and regretted it.

"Travis [Kalanick] is one of my best friends, but I missed the early rounds," Mikitani said, laughing. "I should have invested in Uber, but I missed."

Mikitani then continued on to explain why he ended up investing in Lyft, Uber's $2.5 billion rival.

"Lyft is more social, more real-ride sharing," he said.

He also complimented the founders, saying that he was impressedby the company culture that they had created.

And, he added: "Their attitude is much friendlier than their competition."

A few months ago, Lyft announced a partnership with Chinese Uber rival Didi Kuaidi. Starting early next year, you'll be able to pay in your native currency on each app to avoid having to pay for your Didi or Lyft ride in a foreign currency, depending on where you live.

So if you're an American visiting China, you can open the Lyft app to pay for and order a Didi, and then Lyft will give whatever money it made from your ride to Didi.

And last week, both companies jointly announced an expanded partnership with India's Ola and Singapore's GrabTaxi, expanding the anti-Uber ride-hailing alliance to more countries.

Mikitani said that, as the CEO of an ecommerce company, he also appreciates the logistic and on-demand insights he's getting from Lyft.

"We need to be in that business to understand the last moment of delivery," he says. "It was a very natural judgment."

Rakuten just launched 20 minute deliveries in Japan.