SINGAPORE -- The co-founder of Grab, which has become one of Southeast Asia's most valuable tech startups in just seven years, says the group's ride-hailing and payment business can help society while making financial sense. Tan Hooi Ling stressed that the ideas of a "path to profitability" and "sound unit economics" -- phrases often heard in the valuation debate over U.S. tech groups like Uber Technologies and WeWork -- are "not new" to Grab.