It sounds like you had a specific pitch that you gave. Do you think that people would be more willing to join as a co-founder if they had some input on the original idea?
That goes both ways: I respect the amount of work it takes to make a company financially stable and to strategically position it in the marketplace. It seems to me that the engineers running businesses have been successful only because they picked up business skills along the way, but perhaps it is more efficient to partner with someone who already has those skills.