Universities have shifted their funding models towards running like a business: having their core operations directly generate income. This contrasts the traditional format in which the university provides society with a wide variety of trained people whose actions generate wealth, part of which gets invested back into the university. Rather than being invested in, students have become the principal customer and thus have borne a dramatically increased financial burden, tuition doubling every ten years. Among other questions, this brings up the issue of how universities convince students to keep attending as costs skyrocket.