You can only write an exhaustive spec if you know what you want - and no startup, and most software projects in general - have no freakin idea what they want 'u

You can only write an exhaustive spec if you know what you want - and no startup, and most software projects in general - have no freakin idea what they want 'up front.' Thats why BDUF failed and hardly anyone uses it anymore. You have to use a prototype to know what you really want and even the prototype changes as you build it. Its an iterative process, and one that requires an intuitive developer as well as customer contact. And you can't get that using elance. Building good products requires technical intuition that you can't rent.