If you want to grow, you need new customers. And if you want new customers, you need three things:
1. A group of possible customers you can identify and reach.
2. A group with a problem they want to solve using your solution.
3. A group with the desire and ability to spend money to solve that problem.
You'd be amazed at how often new businesses or new ventures have none of these. The first one is critical, because if you don't have permission, or knowledge, or word of mouth, you're invisible.
The Zune didn't have #2.
A service aimed at creating videos for bestselling authors doesn't have #1.
And a counseling service helping people cut back on Big Mac consumption doesn't have #3.