I can't agree more. First you need a product that works at least for some users, then when you are expanding the user base it's time for dashboards.

Dashboard answers the question: Is my product right now working for my users?

Eventually it can also show trends in terms of resource usage, strange peaks, etc. But the primary function of dashboard is answering the question: "are my users getting the service?"

Additional note: dashboard works wonders for getting us - engineers - understand that there are real users out there right now and thus making us want to build even better product.