They increased their top-line revenues by ~10x over the last three years, but they also increased their sales and marketing expense by ~10x over the same time p

They increased their top-line revenues by ~10x over the last three years, but they also increased their sales and marketing expense by ~10x over the same time period. Call me crazy, but I'm guessing that "sales & marketing" spend is mostly sales, and they're essentially buying revenue right now. That strategy can work, but it remains to be seen if revenue growth will continue once the sales spending slows (i.e. if the sales operation will become more efficient). If they can't make the revenue graph separate from the costs graph, they're cooked.