- What's the one thing that needs to happen for this project to succeed? If there is one key thing, that's good. If there are five or six key things, then you h

- What's the one thing that needs to happen for this project to succeed? If there is one key thing, that's good. If there are five or six key things, then you have a domino rally business, and that's bad: http://redeye.firstround.com/2006/09/domino_rally_bu.html http://redeye.firstround.com/2006/09/domino_rally_bu.html - What's the engine of growth? The best businesses basically start with the engine of growth and then work backwards to find a product. If the product doesn't have a built-in mechanism of virality, then you should be asking yourself how easy it will be to get leads, since that's the most important determinant of CAC. Again start by finding a great source of valuable leads, and then build the product to match. - What are the assumptions, risks, and unknowns? Specifically in the areas of user engagement, growth, design, technology, and monetization. If this list is less than, say, three pages, then you're probably not engaging with the idea at a deep enough level yet to be capable of successfully executing. - Is this a good idea for you? In the above section I'm assuming there isn't any significant founding team risk because you're doing a startup that's well-suited to your skillset; if not, it's not a good idea for you. Remember, everyone is capable of running a successful business, even if it's only a hotdog stand; the trick is finding an idea that's just at the edge of your current skillset. - What are the key metrics I need to hit for a seed round, series A, series B, etc? And similarly, what are the key assumptions, risks, and unknowns that I need to figure out before each of those rounds? - What skills would I need to acquire to successfully run this business? E.g. if it's a web startup you need to know how to code, if it's a biotech startup then you need to know biotech, etc. In order for the business to be viable you need to have the skills to do the hard part yourself, for whatever that means for the given idea. You can hire more people to help you do the hard part faster, but you can't hire them for something that you don't already (mostly) know how to do yourself.