Large companies reinvest most of their profits as bets on the future — building new arms of the company, that initially do nothing but quiet R&D for months/year

Large companies reinvest most of their profits as bets on the future — building new arms of the company, that initially do nothing but quiet R&D for months/years — but which might bring the company entirely new revenue-lines years down the line. Much of a large company's headcount at any point in time, is people hired to work on these bets on the future. You can fire all of these people, and nothing will happen to the company's day-to-day operations. But the company's stock will take a nosedive nevertheless — because the promise of future increased returns had already been factored into the share price, and that factor now has to be removed.