At 23, Shunji Sugaya had what he calls a "life-changing episode.”

It was March 2000, and Sugaya had just won an award at a business contest where Masayoshi Son, the founder of what was then called SoftBank Corp., was a judge. He sent Son an email to thank him, the two met up, and before long SoftBank offered to buy Sugaya’s idea for $2.8 million or for Sugaya to join the company and receive stock options.

Sugaya turned it down.