Or, not exactly unheard of, they aim at finding a buyer for themselves well before a time when it may become clear whether the product would really be viable or

Or, not exactly unheard of, they aim at finding a buyer for themselves well before a time when it may become clear whether the product would really be viable or not. In those cases the product is the company itself and they don't need to have a finalized working and useful real product. Works especially well in "hype" topics where hope can more easily win against common sense (of the buyer).