Personally, I think that any product, successful or otherwise, is a unique combination of the sum of its parts. In some cases, that equation is more heavily driven by the technology end, others by the business end, and others by the maintenance and support. I don't see that any simple equation will work for every situation. I think that's the basic reason that understandable frustration builds up on all sides of the equation- the symptoms of the problem being lack of understanding/appreciation of the function of the other elements since they are all so subjective to the situation, and most people in one 'silo' don't really want to know about the other parts of the business. At least, that's what I've seen, and know that I'm guilty of.