Why Ola co-founder Bhavish Aggarwal spurned existing investor SoftBank's $1.1b offer

Startups, when they raise venture money to build their businesses, begin with a Series A round and then proceed through Series E, F or maybe G before going public. The Indian ride-hailing service Ola is a bit unusual: It just completed its Series J fundraising and is marching toward Series K, a letter almost unheard of by researchers that track such things.