It happens way too often: entrepreneurs proud of some huge completely unattainable market numbers. They show us billions of dollars. They think that’s a good thing, like it’s important. I hate it.

As an investor, as a business plan contest judge, or as a teacher, I don’t really care how many billions of dollars are spent on this or that or the next thing when I’m reading a business plan. That number is too big. It tells me nothing. Startups don’t reach multi-billion dollar markets.

If it makes you feel better to give me that number in passing, okay, go ahead, but don’t put any emphasis on it. Instead, give me the details on how you’re going to make your sales, and to whom, on the first day, the first quarter, and the first year. Give me granularity.

If you’re a Web-based startup, for example, show me how many unique visitors you think you can get in the beginning, and what you’re using for an estimated conversion rate (buyers to browsers). Show me how much each unique visitor is going to cost you in search engine optimization and pay-per-click search engine expense.

If you’re a restaurant, for example, show me how many chairs and tables lead to what assumptions for first-day, first-month, and first-year meals served, drinks served, and at what average price. Show me how you’re going to bring those people in the door.

I guess what this means is that I like forecasts that build from the details up to the larger numbers.

And I know that I’m in the majority, among people who read business plans, in really disliking the top-down, billions and billions kind of forecasts. When they start talking about getting only a very small percentage of an enormous market, they lose me. Those huge markets don’t split down into millions of pieces.