I think this is a mistake. The correct approach would be to throw as much money at it as needed while the hype train is rolling to gain users and worry about monetization later. It's not like the market share gain won't pay for itself. They are worrying about controlling costs for a product that hasn't launched to limit the interaction of users they don't have yet. They have spent billions on a search engine that nobody uses, why not spend some money on something that actually has potential?