Under a successful support driven model, engineering costs associated with fixing bugs and quirks in the product are amortized across all clients. Fixing a bug for one user fixes it for another, as well as future users. However, if the paid user base is not sufficient to cover support costs, VC money is effectively subsidizing support.

In the spirit of analyzing your business model, how much of your success has come about because you had access to a subsidized team fixing bugs for you?