Bums on seats is what is crucial. The thorny issue of how to get paying customers through the front door, is one that should be addressed - and solved - before any new venture is embarked upon.
And this is intricately involved with the substance of the venture itself. What is it that is on offer, are people likely to want it , and will people pay sufficiently to enable the business case to stack up in the real world? Take three brain-waves out the trillions that are conjured out of thin air each year: a computer networking consultancy; a child care establishment; and, a retail photography venture.
There is certainly a demand for child care places, but parents are loathe to pay the economic cost, thinking it to be little more than baby-sitting, and besides they can do it themselves. There is certainly a market for photography, but most people contend they can do just as well themselves, and portraiture is so very subjective.
Which leaves us with networking computers.