Venture capitalists are mostly drawn to ideas/projects that are protected from competition -- that's why so much of their money goes into start-up drug companies and software development. Both categories offer patent and copyright protection.
Yes, you can try to patent a widget but it's pretty easy for a competitor to change a widget enough that you patent is nearly useless. Much harder to do with drugs and software.
Venture money is also very leery of any idea that relies heavily/solely on one person (or a very small group of people). Their agreement will say that if the company dissolves, they own all the assets (i.e. all the work product, research, etc). But, if one person is The Asset, that clause of the agreement means nothing for them....so they won't do it.
It's impossible to be more specific without knowing the idea.