HONG KONG/TAIPEI/TOKYO -- It was during a two-month trip to Africa last year that Jack Ma Yun realized it was time to step down as the captain of Alibaba, the powerful Chinese technology company he had founded in his apartment nearly two decades earlier. While Ma was off meeting African heads of state and pushing his $10 million fund to encourage entrepreneurs on the continent, the world's largest e-commerce company was humming along just fine without him.