Bob provides some very good solid advice for starting entrepreneurs. On his first point about knowing your market size, I think this is a very important point as most startups are grappling with their market opportunity, especially in the early stages. When talking about market size and your market share potential, VCs are not interested in hearing your company would be successful if you captured "just 3%" of a trillion dollar market. Narrow down the real opportunity, VCs would prefer companies that can be market share leaders with well over 50% market share in a smaller but rapidly growing market. Leading companies such as Apple, Google, and Cisco all aspire to be the far and above market share leader in their various service and product offerings and successful startups should have that same mentality.