There are oil refineries that are decades old and still generate plenty of cash for their owners (granted, they need maintenance investments, but the bulk of the investment is certainly at the beginning), the same goes for cargo ships etc... While FB and GOOG need to come up with a new product or service every 6 months to keep those customers (see SNAP and their allegedly better fit with younger users). And MSFT wasn't in a very healthy situation just a few years ago. I have of course generalised and things are never clear-cut: servicing the high debt used to finance initial capital is also quite risky.